For your info:
I just wanna mention that EasyPark seems to have updated their Android App so it works on /e/OS 
Reason for previous issues was (I think) that EasyPark used the Sinch SMS library to receive the verification SMS, but assumed that Google Services would display the incoming SMS.
Since Google Services is not available, the verification SMS never got displayed, thus you could not register the EasyPark app on the phone.
This seems to be fixed now
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