Apple Watch STILL not working for payment on London tube

I could see a conversation chain on this subject but nobody had commented in two years.

My Series 6 watch was only bought in Dec 2020. I visited London to change trains on two days last week and used my watch to tap in and out. It seemed incredibly easy at the time.

However, it wasn’t successful on either occasion. As a result, I was charged twice on the first day and was charged the ‘didn’t tap out’ penalty on the second. Tfl have since refunded these amounts and advised me to revert to using my actual credit card to tap in and out on future occasions.

As instructed, before travelling, I had assigned my Apple pay credit card as my travel pay card on the watch and I used my watch, not my phone, to both tap in and out.

Could someone therefore advise if I needed to do anything else - or why is this system still unreliable?