diff --git a/CHANGELOG.md b/CHANGELOG.md
index fce1de5f..39884a10 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,7 @@
     * Added a `min_height:` option for list field
 1. [](#bugfix)
     * Fixed z-index issue for tooltips in sidebar
+    * Fixed custom files being overridden during theme update [#2135](https://github.com/getgrav/grav-plugin-admin/issues/2135)
 
 # v1.10.13
 ## 04/23/2021
diff --git a/classes/plugin/AdminController.php b/classes/plugin/AdminController.php
index 04413ba8..6c10f497 100644
--- a/classes/plugin/AdminController.php
+++ b/classes/plugin/AdminController.php
@@ -993,7 +993,7 @@ class AdminController extends AdminBaseController
             return false;
         }
 
-        $result = Gpm::install(array_keys($dependencies), ['theme' => $type === 'theme']);
+        $result = Gpm::install(array_keys($dependencies), ['theme' => $type === 'themes']);
 
         if ($result) {
             $this->admin->json_response = ['status' => 'success', 'message' => 'Dependencies installed successfully'];
@@ -1033,7 +1033,7 @@ class AdminController extends AdminBaseController
         $data = $this->post;
         $package = $data['package'] ?? '';
         try {
-            $result = Gpm::install($package, ['theme' => $type === 'theme']);
+            $result = Gpm::install($package, ['theme' => $type === 'themes']);
         } catch (\Exception $e) {
             /** @var Debugger $debugger */
             $debugger = $this->grav['debugger'];