Npcs not giving quest items

[BufusTurbo92]

Hi, recently npcs have stopped giving me quest items. For example, Taarie won't give me the outfit to show Elisif. The log states the following:

[12/29/2018 - 11:40:08PM] ERROR: Cannot call Enable() on a None object, aborting function call
stack:
[solitudeFreeform02 (000C7D1C)].QF_SolitudeFreeform02_000C7D1C.Fragment_0() - "QF_SolitudeFreeform02_000C7D1C.psc" Line 34
[12/29/2018 - 11:40:08PM] ERROR: Cannot add None to a container
stack:
[ (00000014)].Actor.AddItem() - "<native>" Line ?
[solitudeFreeform02 (000C7D1C)].QF_SolitudeFreeform02_000C7D1C.Fragment_0() - "QF_SolitudeFreeform02_000C7D1C.psc" Line 35

I tried moving mods around (although I have not installed any new ones for some time and the problem has arisen only in the last couple days), reinstalling the unofficial patch, running LOOT, validating game files, redownloading skyrim.esm and update.esm, but nothing has solved the issue.

Can anybody help me?