diff --git a/CHANGELOG-v3.md b/CHANGELOG-v3.md
index 4d63af275b5..5a2ae78deb4 100644
--- a/CHANGELOG-v3.md
+++ b/CHANGELOG-v3.md
@@ -5,6 +5,7 @@
 ### Fixed
 - Fixed a bug where renaming an asset file was impossible using the element action. ([#3707](https://github.com/craftcms/cms/issues/3707))
 - Fixed a bug where saving user details would result in a PHP error.
+- Fixed a bug where it was impossible to apply project config changes. ([#3713](https://github.com/craftcms/cms/issues/3713))
 
 ## 3.1.4 - 2019-01-24
 
diff --git a/src/services/ProjectConfig.php b/src/services/ProjectConfig.php
index cdd0d578898..c8ea44b8dfa 100644
--- a/src/services/ProjectConfig.php
+++ b/src/services/ProjectConfig.php
@@ -665,7 +665,7 @@ public function getAreConfigSchemaVersionsCompatible(): bool
         $existingSchema = (string)Craft::$app->schemaVersion;
 
         // Compare existing Craft schema version with the one that is being applied.
-        if (version_compare($existingSchema, $incomingSchema, '=')) {
+        if (!version_compare($existingSchema, $incomingSchema, '=')) {
             return false;
         }
 
@@ -677,7 +677,7 @@ public function getAreConfigSchemaVersionsCompatible(): bool
             $existingSchema = (string)$plugin->schemaVersion;
 
             // Compare existing plugin schema version with the one that is being applied.
-            if (version_compare($existingSchema, $incomingSchema, '=')) {
+            if ($incomingSchema && !version_compare($existingSchema, $incomingSchema, '=')) {
                 return false;
             }
         }