Cannot read this valid QR-Code

[frankmer]

I tried to scan a QR code from Google Authenticator, but I got a 'FormatReaderException' error.

Used was this Function:
QRCodeReader().decode(bitmap);

My code successfully scanned other QR codes generated by Google Authenticator or other apps.
Only this code didn't worked for me.
Other QR scanners had no issues reading this code.