I had a guy with position do this instant minraise to me three times in the period of an hour.

The scenario was always a HU flop, I'd cbet 3/4 pot and he'd instant minraise me. The first two times I reraised him standard and he folded, but the third time, I thought maybe he was trying to induce my raise.

Would you say he's just a donk with a minraise habit, or did I make the right move by not 3-betting again with air?