diff --git a/plogical/customACME.py b/plogical/customACME.py
index e769e8c7d..cf93c23d9 100644
--- a/plogical/customACME.py
+++ b/plogical/customACME.py
@@ -4,6 +4,7 @@ import time
 import requests
 import base64
 import hashlib
+import hmac
 import logging
 from cryptography import x509
 from cryptography.hazmat.primitives import serialization
@@ -92,7 +93,20 @@ class CustomACME:
         try:
             logging.CyberCPLogFileWriter.writeToFile('Getting new nonce...')
             response = requests.head(self.directory['newNonce'])
-            self.nonce = response.headers['Replay-Nonce']
+            
+            # Check for nonce in headers (case-insensitive)
+            nonce_header = None
+            for header_name in ['Replay-Nonce', 'replay-nonce', 'REPLAY-NONCE']:
+                if header_name in response.headers:
+                    nonce_header = header_name
+                    break
+            
+            if not nonce_header:
+                # Log all available headers for debugging
+                logging.CyberCPLogFileWriter.writeToFile(f'Available headers: {list(response.headers.keys())}')
+                raise KeyError('Replay-Nonce header not found in response')
+            
+            self.nonce = response.headers[nonce_header]
             logging.CyberCPLogFileWriter.writeToFile(f'Successfully got nonce: {self.nonce}')
             return True
         except Exception as e:
@@ -244,6 +258,27 @@ class CustomACME:
                 "contact": [f"mailto:{self.admin_email}"]
             }
             
+            # Check if External Account Binding is required (for ZeroSSL)
+            if self.provider == 'zerossl' and 'meta' in self.directory and 'externalAccountRequired' in self.directory['meta']:
+                if self.directory['meta']['externalAccountRequired']:
+                    logging.CyberCPLogFileWriter.writeToFile('ZeroSSL requires External Account Binding, getting EAB credentials...')
+                    
+                    # Get EAB credentials from ZeroSSL
+                    eab_kid, eab_hmac_key = self._get_zerossl_eab_credentials()
+                    if not eab_kid or not eab_hmac_key:
+                        logging.CyberCPLogFileWriter.writeToFile('Failed to get ZeroSSL EAB credentials, falling back to Let\'s Encrypt')
+                        # Fallback to Let's Encrypt
+                        self.provider = 'letsencrypt'
+                        self.acme_directory = "https://acme-v02.api.letsencrypt.org/directory"
+                        if not self._get_directory():
+                            return False
+                        if not self._get_nonce():
+                            return False
+                        return self._create_account()
+                    
+                    # Add EAB to payload
+                    payload['externalAccountBinding'] = self._create_eab(eab_kid, eab_hmac_key)
+            
             jws = self._create_jws(payload, self.directory['newAccount'])
             if not jws:
                 logging.CyberCPLogFileWriter.writeToFile('Failed to create JWS for account creation')
@@ -284,6 +319,90 @@ class CustomACME:
             logging.CyberCPLogFileWriter.writeToFile(f'Error creating account: {str(e)}')
             return False
 
+    def _get_zerossl_eab_credentials(self):
+        """Get External Account Binding credentials from ZeroSSL"""
+        try:
+            logging.CyberCPLogFileWriter.writeToFile('Getting ZeroSSL EAB credentials...')
+            
+            # Request EAB credentials from ZeroSSL API
+            eab_url = 'https://api.zerossl.com/acme/eab-credentials-email'
+            headers = {
+                'Content-Type': 'application/x-www-form-urlencoded'
+            }
+            data = {
+                'email': self.admin_email
+            }
+            
+            response = requests.post(eab_url, headers=headers, data=data)
+            logging.CyberCPLogFileWriter.writeToFile(f'ZeroSSL EAB response status: {response.status_code}')
+            logging.CyberCPLogFileWriter.writeToFile(f'ZeroSSL EAB response: {response.text}')
+            
+            if response.status_code == 200:
+                eab_data = response.json()
+                if 'eab_kid' in eab_data and 'eab_hmac_key' in eab_data:
+                    return eab_data['eab_kid'], eab_data['eab_hmac_key']
+            
+            return None, None
+        except Exception as e:
+            logging.CyberCPLogFileWriter.writeToFile(f'Error getting ZeroSSL EAB credentials: {str(e)}')
+            return None, None
+
+    def _create_eab(self, eab_kid, eab_hmac_key):
+        """Create External Account Binding for ZeroSSL"""
+        try:
+            logging.CyberCPLogFileWriter.writeToFile('Creating External Account Binding...')
+            
+            # Get the private key numbers
+            private_numbers = self.account_key.private_numbers()
+            public_numbers = private_numbers.public_numbers
+            
+            # Convert numbers to bytes
+            n_bytes = public_numbers.n.to_bytes((public_numbers.n.bit_length() + 7) // 8, 'big')
+            e_bytes = public_numbers.e.to_bytes((public_numbers.e.bit_length() + 7) // 8, 'big')
+            
+            # Create JWK
+            jwk = {
+                "kty": "RSA",
+                "n": base64.urlsafe_b64encode(n_bytes).decode('utf-8').rstrip('='),
+                "e": base64.urlsafe_b64encode(e_bytes).decode('utf-8').rstrip('=')
+            }
+            
+            # Create protected header for EAB
+            protected = {
+                "alg": "HS256",
+                "kid": eab_kid,
+                "url": self.directory['newAccount']
+            }
+            
+            # Encode protected header
+            protected_b64 = base64.urlsafe_b64encode(
+                json.dumps(protected).encode('utf-8')
+            ).decode('utf-8').rstrip('=')
+            
+            # Encode JWK payload
+            payload_b64 = base64.urlsafe_b64encode(
+                json.dumps(jwk).encode('utf-8')
+            ).decode('utf-8').rstrip('=')
+            
+            # Create signature using HMAC-SHA256
+            signature_input = f"{protected_b64}.{payload_b64}".encode('utf-8')
+            hmac_key = base64.urlsafe_b64decode(eab_hmac_key + '==')  # Add padding if needed
+            signature = hmac.new(hmac_key, signature_input, hashlib.sha256).digest()
+            signature_b64 = base64.urlsafe_b64encode(signature).decode('utf-8').rstrip('=')
+            
+            # Create EAB object
+            eab = {
+                "protected": protected_b64,
+                "payload": payload_b64,
+                "signature": signature_b64
+            }
+            
+            logging.CyberCPLogFileWriter.writeToFile('Successfully created External Account Binding')
+            return eab
+        except Exception as e:
+            logging.CyberCPLogFileWriter.writeToFile(f'Error creating External Account Binding: {str(e)}')
+            return None
+
     def _create_order(self, domains):
         """Create new order for domains"""
         try: