Hey Taj,
Is the tape flanging (that's what the problem you have is called) on the outside or inside?
If it's on the outside, you may need to use a pair of "reel spacers" to move the reel out a tiny bit. Most "pro-sumer" machines use these and if United didn't supply you with a pair, you should probably contact them to see if you can get a pair.
The reason for the spacers is the difference in the thickness of plastic and metal reels. If the reel tables are adjusted so the plastic reels don't flange, then the metal reels will on some tapes because of normal tape "wandering". Also, the interface between the inside flange of the reel and the turntable surface is not exact so there's always a tiny bit of wobble as the reel turns. At one point or another, this tape "wandering" and the reel "wobble" will combine to make the tape rub the flange.
I have to use a pair of "spacers" with my Technics and most folks with machines that were intended to play plastic and metal reels will also.
Of course, you can have your reel tables adjusted for metal reels but then you'll get considerable flanging with plastic ones and in that case, a spacer would only make it worse.
If the tape is flanging on the inside, the reel tables probably need adjustment.
It could also be a problem with the NAB hub adapter. If the rubbing is only on the take up side, try switching the adapter from side to side and see if that helps. Some of those adapters don't work so great with all reels and increase reel wobble.
I've got all the TP tapes and I'm pals with several other subscribers. I've never heard of anyone having a problem with bent or warped reels.