potty training 9-week old frenchie; indoor apartment

hi!

we recently adopted a male frenchie puppy at 6 weeks, he is now 9 weeks. (early, i know but he came from a friend who was emergently moving and needed to home the babies)

we live in a mostly carpeted apartment, save for the kitchen tiles & bathrooms. at the advice of our vet, puppy is on “house arrest” while he completes his vaccines schedule (18 weeks— so 9 more weeks to go…) as all the grass areas in our complex are high dog traffic areas.

i work from home and am home with him all day long save for the hour or so while i go to a workout class (he stays gated in the kitchen tiled area)

at first he was doing well with puppy pads in the kitchen, but within the last week or so his 80% accuracy on the pad has fallen to basically only one time a day. we immediately praise and reward with treats when he goes on the pad, but within the last week he’s taken to going anywhere except the pee pad; carpet, tile, the kitchen mat we stand on at the sink.

if i catch him squatting, i interrupt and immediately bring him to the pee pad, but he will just sit or lay there (for upwards of 15-20 minutes) until he can run off to play again and eventually try to potty elsewhere.

any tips or tricks to get him back on the pee pad?

i did order one of those faux grass pee pads which should be here tomorrow, to put on our patio to make the eventual transition to outside easier.