Umarex Airem 2 (aka Ruger Airhawk 2)

Hi all, my first post on the forum so go easy on me please :) and I apologize in advance if this post is in the incorrect area. I'm a new Air rifle owner from South Africa
I currently have a few air rifles, most recent purchase, a Nitro Piston Airem 2 by Umarex, the rifle has been acting up I would say 200-300 shots in and the erratic behaviour started. I just cannot seem hit anything i aim at regardless of distance. I realised the forestock bolts were loose and stripped, replaced them with new ones and some loctite. No difference, so today i stripped the rifle down and found the piston seal which doesnt look right to me. Please can anyone with experience using this rifle or similar, provide some input on this seal? Looking at other brands the seals seem complete with no notches in it, do i perhaps have a damaged seal?

Thanks so much!
Umarex_Piston_seal1.jpg
Umarex_Piston_seal2.jpg
 
Hey Bob thanks, I thought so, apologies for what may have seemed like a silly question, its the first time I have seen the seal from a Air Rifle lol, im really stumped as to how this happened I am almost convinced it was damaged when it was inserted already, but alas now that i have opened her up my warranty will be void. Finding spares also seems to be a challenge here in South Africa, not many retailers keep parts. I have opted for a new Rifle (A Kuzey TX-2) that is on its way, that will at least give me something to have fun with while i try to source parts for the Umarex 👍