In-app-purchases are not verified on Shiftphone 6mq

On my Fairphone 3 with /e/OS 2.2-t-stable all apps with in-app-purchases are correctly verified if I log in with my Google account in App Lounge.
On my Shiftphone 6mq with /e/OS 2.2-t-dev none of these apps gets verified so that I cannot use the bought features there.
I wrote to the help desk twice already but no answer within several weeks.
Any idea what might be the cause?

Here is another issue (about a German app) with microG on the Shiftphone 6mq which works correct on the Fairphone 3.

Maybe that’s the reason:

Thank you for your answer.
I forgot to write that both phones are rooted and therefore SafetyNet is disabled because it fails anyway. Because purchase verification works on the Fairphone 3 SafetyNet seems not to be necessary for it.

Although SafetyNet is disabled, do you think your Google account will still check your device for certain “markers”?

This post mentions diffs that you might compare between the devices.

That’s interesting. I read about this before but did not think it might apply to this problem because SafetyNet is disabled.
But the Kernel name of the Shiftphone 6mq contains lineage, the one of the Fairphone 3 not.
I will create an issue in gitlab after the helpdesk did not answer.