I have following issue with BV9600 Pro ( BV9600Pro_EEA_S700_V1.0_20190530V8, using 2 SIM cards):
Device functions normally, doesn't show any issues, BUT it isn't possible to make a phone call, receive a phone call or connect to the internet using mobile data. (SIM status for both slots says: Mobile network state: Disconnected) After switching Aeroplane Mode on and off, the phone connects to the network and GSM functionality works OK. (SIM status for both slots says: Mobile network state: Connected) This repeats several times during the day. (some time later I would like to make a phone call or use mobile data and I find it isn't working again).
WiFi network works all the time without issues.