Indevolt Solidflex not responding

Hi, I have been using the official Indevolt app to monitor and control my Solidflex 2000. This worked well for a couple of months, but for a second time now the API suddenly stopped responding. I restarted the app and reïnstalled it, and after a few days it suddenly worked again. Now it stopped once again. What is going on, and how do I get it up and and running again?