( ! ) Fatal error: Uncaught TypeError: MessageBird\RequestValidator::validateSignature(): Argument #1 ($signature) must be of type string, null given, called in C:\wamp64\www\common\messagebird\src\MessageBird\RequestValidator.php on line 194 and defined in C:\wamp64\www\common\messagebird\src\MessageBird\RequestValidator.php on line 133
( ! ) TypeError: MessageBird\RequestValidator::validateSignature(): Argument #1 ($signature) must be of type string, null given, called in C:\wamp64\www\common\messagebird\src\MessageBird\RequestValidator.php on line 194 in C:\wamp64\www\common\messagebird\src\MessageBird\RequestValidator.php on line 133
Call Stack
#	Time	Memory	Function	Location
1	0.0006	451992	{main}( )	...\signed-request-validation.php:0
2	0.0013	539664	MessageBird\RequestValidator->validateRequestFromGlobals( )	...\signed-request-validation.php:10
3	0.0013	540656	MessageBird\RequestValidator->validateSignature( $signature = NULL, $url = 'https://mksmc.ddns.net/common/messagebird/examples/signed-request-validation.php', $body = '' )	...\RequestValidator.php:194