Mobile suddenly switched off & not booting

Hi,
My mobile suddenly switched off while using. SOS few other apps opened automatically & suddenly crashed & not booting. Tried to restart. Stuck with Blackview & android logo & this screen is running every 2 mins.

RED notification LED is blinking repeatedly.

Please help.

I didn't find the right solution from the Internet.

References:
bbs.blackview.hk/viewtopic.php?t=360908
Online Video Pricing

Thanks