diff --git a/phpdoc.php b/phpdoc.php
index <HASH>..<HASH> 100644
--- a/phpdoc.php
+++ b/phpdoc.php
@@ -593,6 +593,10 @@ foreach ($carbonMethods as $method) {
         $return = '';
     }
 
+    if ($method === '__toString' && $phpLevel < 8) {
+        $return = '';
+    }
+
     if (method_exists($function, 'getAttributes') && ($attributes = $function->getAttributes())) {
         foreach ($attributes as $attribute) {
             $methodDocBlock .= "\n    #[".$attribute->getName().']';
diff --git a/src/Carbon/CarbonInterface.php b/src/Carbon/CarbonInterface.php
index <HASH>..<HASH> 100644
--- a/src/Carbon/CarbonInterface.php
+++ b/src/Carbon/CarbonInterface.php
@@ -742,7 +742,7 @@ interface CarbonInterface extends DateTimeInterface, JsonSerializable
      *
      * @return string
      */
-    public function __toString(): string;
+    public function __toString();
 
     /**
      * Add given units or interval to the current instance.
Fix __toString interface compability