ZV8 internal sd card issues topic

I don't know if this is sd card issue or what but many of the apps are not able to write data on phone. For e.g. whatsapp not able to download media, swiftkey not able to download language pack, chrome not able to download.
I flashed zv4 tot to restore all the partitions but still no luck.
This is only happening on ZV8 and not on ZV6 and ZV4.

Any help will be highly appreciated.