Can't delete files from sd card

[Shreyas Venkat]

I upgraded my Samsung galaxy a5 from earlier version of marshmallow to a newer one.
Before upgrading sd card was not locked or anything , but when i upgraded i couldn't delete files from my sd card.
However after removing and reinserting the sd card i could delete files but after a day the problem reappeared.
What should I do?

 

[B. Diddy]

Are you using My Files to delete files, or a 3rd party file manager app?

 

[Shreyas Venkat]

3rd party

 

[Shreyas Venkat]

But even in my files it says unable to delete