Contactless not working on buses?

As a bus driver I see a lot of declined Apple Pay google pay transactions and just ask if have card 9 times out of 10 the card is produced and transactions fine
Possibly something to do with…
Phone placed for payment machines reads data/signal has to go from either ticket machine or phone to either Apple google servers then MasterCard visa servers To bank server and ticket machine in a very small window?

I’ve always had monzo via Google pay fail in Dunnes stores in Belfast. Although I also tried Halifax credit via Google pay and it failed too! So I’m wondering if they have their terminals setup wrong. I messaged them on FB and they said they’d look into it. Both MasterCard too.

It has been over half an hour for me

Haven’t tried Monzo since, but Dunnes did accept my Virgin CC MasterCard through Apple Pay above the £30 limit the other day.