Vicare Viessman: Unknown error

I try to install the Viessmann integracion. After sendeing the complete input form it returns with “unknown error”.
What could be the reason? All data are correct.

My integration has stopped working this morning. Might not just be you.

Last night my boiler restarted and I had to setup WiFi again.

Today I’m on WiFi and the ViCare app works but HA isn’t getting any info.