I have got the same problem on the ps4 it also started yesterday! i make a manual safe after every mission i complete butt this one doesnt work also after reloading my safe file.
I had about 4 main mission that got bugged on me and could recover them after downloading my save file.
I am playing solo and i like the game butt this sucks.
Trying now for hours to find a solution how to get it completed butt nothing works.
This seems to be the only mission I have bugged where it just won’t register that it’s completed.