Problem Deleting Append Structure from table MARA.

Hello Experts,

I had on Append structure in MARA table which I deleted by clicking on Append structure -> Selecting the append Structure.

The Append Structure is deleted now if I try to view it from SE11, But it is still visible in MARA and I am unable to activate the MARA table.

I tried Adjusting the Table but this results in Error as above.