API Stopped working

Hi, I'm no longer receiving Data via the API since yesterday. 
APIUser Login is still working (tried with Powershell+ChatGPT, Login was fine).
Every Sensor is "Unknown", APIUser's Deadline is 2099-12-31 09:27:22.
There was no Problem in the last 1-2 years, suddently it stopped, without changing anything in the FusionSolar Webportal.