Inkbird ISC-007BW switches off every time during sessions

After using this device without any problems the last half year (when I bought it) lately the device switches off, so instead thinking the bbq is heating up nothing happens, no fan etc. I have to turn the switch in the app to On every time (or on BBQ on the device itself). Thatś not how is suppose to be, niw I can rely on the device. That;s where I bought it for. Itś unthinkable a nigt session would fail because of the device switching off. So it has power, it’s on but not switched on. Any thoughts on this? is the device broken?

Edit: today I started with the app on while prepping stuff inside the house. After done went outside and shut down the app. It didn happen anymore, it looks like the app is turning the device off?

edit 2: after some time this seems not to be the cause:also without the app the device switches off.

edit 3: also no graphs possible, so something is way off here,

So, what cab I do about it? This way I can’t use the device as it is intended to be.

Please check whether the probe of ISC-007BW is plugged in tightly? Does ISC-007BW show the probe reading?
Please check whether the time function is set? Please understand that if the time is 0:00, ISC-007BW will turn off the fan.
If it still has problems, please provide the link to this post, order information and product problem video to email for after-sales service.