2FA Setup in PHP will not scan QR code on iOS

I am using this documentation on setting up 2FA for my web app.

https://github.com/Voronenko/PHPOTP/wiki/Simple-PHP-implementation-of-two-factor-authentication

I have managed to implement it fine and i am using the Authy app which works great on Android, however when trying to scan the QR code on an iOS device, its saying the QR Code is invalid.

I cannot work out why its saying the QR Code is invalid.

I am using this PHP code to generate the QR code:

print sprintf('<img src="%s"/>',TokenAuth6238::getBarCodeUrl('user', 'url', $secretkey, 'issuer'));

There are no problems on Android, iOS will work to generate the authentication code and verify when setup using the key manually but the QR just will not scan.

Does anyone have any ideas what could cause this to happen?

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