Bought 2nd hand 29er on one wheel, superlight hub and when mounted it in the bike found it has a bit of waggle

tried tightening the caps at either side but still has movement-am i missing something really straightforward?

ta

If clamped in the frame, lift the rear wheel, grasp at 12 and 6 o’clock, puch/pull in opposite direction between each hand. If it waggles and knocks it’s likley to be the bearings.

Are they cartridge or cup&cone?

Or you might have a bent axle I suppose but it usually presents a little differently.

cartridge i think, not the smoothest bearings ive ever felt so might be that