Am unable delete format add files to my memorycerd wat to do?

Retrieve what you can from the card then bin it and buy a new one. It is becoming unreliable and I'm sure you don't want to risk using it anymore - I certainly wouldn't.
It will only get worse until eventually you'll be taking some photos with it and they'll all be corrupt and no good.

reset the NTFS permissions on the card then you should be able to format the device.