Deleted and hidden songs reappear

I have about 136 songs most duplicates but not all which I deleted and Hid from my library. This is absolutely fine

However today they all reappeared and seem to take up about 680mb of space

They all have the cloud tag

I cannot now delete them or hide (if I try they just reappear) HOW do I hide them they are shown as hidden on my account

What have you done?