I had a TX200 which shot accurately from the box, but then started throwing flyers as usage increased.
I cleaned the barrel with dry tight pull throughs then a couple with Sovol Autosol and finally a couple with jewellers rouge this resulted in extremely
tight groups much further out than before.
There was a product on the market that was added to the clean bore of a hot barrel, intended for live round guns it nevertheless worked well in air rifle barrels
and cut down the fouling on a friends black powder musket