Good Night, I bought a BV7000 in the gearbest and after some time the device died totally. History is as follows.

After spending a whole day without putting the phone to charge I put the device to charge at night as I do from the first day of use, I was using it with the charger plugged in the night, I went to sleep and I let it load. The next day upon waking I went to get Blackview so I could use it and was surprised at it in a looping process, I watched the loop twice until the device turned off its screen permanently until today. Plug it into the charger and do not turn on the charging led. I tried to reset it by pressing the volume - and the power key but I did not succeed. I tried to plug the device into the computer to open the flash tools but the computer recognizes and ejects the device repeatedly and in a short time.
So far I have not done anything to correct the mistake, but if you know anything I can do thank you for the support. I really liked the device already bought 03 of this and I hope that the others do not have the same defect.

I look forward to your response.

I appreciate your support

A short time connection on PC is normal if you had not start the flash process on PC before. Please try to flash the latest firmware.
If that don't help maybe your battery is defective. In that case contact your seller for repair or exchange.