Background - Started a new position. The person that vacated the position returned, expected the job back but was placed elsewhere. I'm slightly above them in the overall structure of the workplace but not in a direct line of management.
Situation- this person is being extremely difficult. There are lots of procedures that have to come through me or that I need to be in the loop about as part of wider work. I am basically the liason to outside agencies and need to keep relationships with other places. These places have made comments that they are being contacted through inappropriate means by this person and I tried to nip it in the bud by mentioning this to colleague rather than allowing it to escalate to a complaint. Colleague has now started deliberately not putting me on emails an dgenrally ignoring me. I've tried speaking directly to them but they now twist everything I say whilst continuing to circumnavigate me. They either ignore my requests or question everything to a point it takes me way too much rime with them when I have dozens of others at the same level to deal with.
I have spoken to my line manger who just said its just how they are which I'm not wiling to accept!
Any tips on how to deal with someone being deliberately difficult?
Should I just ignore all but the absolute necessary communications or continue to pull them up on their actions?