This is something you better get used to. be Barney Fife and "nip it in the bud"
as others have mentioned the best response is ask for a ride along so they can show you how to improve . They may do that but in my case that usually shut them up.
there are plenty of ways to tell them to friend off without saying the words. When I told them to go on a ride along and they wouldn't I would tell them if they mention my OT again I would file a grievance. ... and then do it.
same as a friend off. Never show weakness.
they left me alone for the most part until a new manager came on board and then they would try. it was funny.
A FedEx "grievance" is a GFT, which means Guaranteed Effed Treatment. It is a TOTAL joke, and only works if you've got some special card you can play. A completely stacked deck in favor of Management and HR, who work together with FedEx Legal in a trifecta of anti-employee games.
There are no Weingarten Rights at FedEx and no legitimate grievance process.
Barney Fife is a Senior Manager at the Mayberry Station BTW.