Can't delete Multi-weapon fighting feat
 

One of my players added this feat, decided they didn't want to go that route... and there's no icon to delete it. This is on a level 4 Operative.

I created a test character, and on that one I have the means to delete it.

Sorry, I haven't come across this myself.

I built a fourth level operative, gave the character Multi-Weapon Fighting feat. and there was an icon on the ABILITIES > FEATS section to delete it... the stop symbol circle with the diagonal slash through it to the right of the feat's listing.

Does your player not see that icon there?

Did this character choose Combat Trick as one of their operative specializations? If so, was Multi-weapon fighting the feat selected for that, rather than as a general feat?

If that's the case, go to the operative tab, find the Combat Feats table there, and delete the feat on that table - you can only delete something from the same table it was added on.