( ! ) Fatal error: Interface 'Swift_Signers_HeaderSigner' not found in /var/www/clients/client0/web4/web/vendor/swiftmailer/swiftmailer/lib/classes/Swift/Signers/DKIMSigner.php on line 16
Call Stack
#	Time	Memory	Function	Location
1	0.0000	363536	{main}( )	.../DKIMSigner.php:0