Xiaomi Mi LED Ceiling Light Smart won't connect to phone

Hi,

A while ago I bought a Xiaomi Mi LED Ceiling Light Smart (45W, 3100lm) and it worked flawlessly but one night it decided to disconnect from the app (I used and still use the Yeelight app and the lamp stayed gray since then).
Now I’m unable to connect it to the phone, I can reset it (7 times for 2 seconds each and the light pulsate for a while but I still can’t connect it to the app…). Now I’m left with only turning it on/off from the power switch…Sometimes (almost every time) it randomly starts to pulsate for 10-20 seconds, it goes 20%brightness to 100%, again 20% and so on…like it knows its not connected…