PHP Errors

Since updating to the latest version, I am getting two PHP errors (one warning, one fatal):

PHP Warning: Undefined variable $submission in .../wp-content/plugins/html-forms/src/class-forms.php on line 333

PHP Fatal error: Uncaught TypeError: HTML_Forms\Forms::get_response_for_error_code(): Argument #3 ($submission) must be of type HTML_Forms\Submission, null given, called in .../wp-content/plugins/html-forms/src/class-forms.php on line 334 and defined in .../wp-content/plugins/html-forms/src/class-forms.php:380