Avast anti-theft issue

Hello,
I am experiencing a weird problem with avast anti-theft on my android device for a couple of weeks.
I am a premium member for months ago and the app used to work like charm but now when I access my.avast portal to control my device it always says “we are unable to connect to you device” whenever I send a commend (see screenshot). However when I use SMS commands it works perfectly. So I think its about connection between device and servers. I tried many time solving the issue but no way, I checked my location service on my device, I tried to solve connection issues from the built-in feature but can’t recieve a message from servers after 20 seconds and finally I reinstalled the app but always the same problem. I even contacted avast custom service but I have not recieve any reply for 3 days.
I am requesting a solution for that issue because the app now seems useless.

Ok, there should be some issues between backend and you, but you will see an error message on the my avast page. Please try to reconnect the device.