Sometimes even perfectly good wheels don't hold air due to bead problems.
I had that problem on all 4 of the alloys on my M5 ! ! Soon sorted by the local
tyre place....deflated the tyres, took tyres off the beads, and they brushed on
some sticky black 'goop' like mastic all round the inner rims edges, then re-inflatted
the tyres. I never had a problem with them after that. I think it cost me £10 at the time.
So to do one wheel....at todays prices....perhaps £5.