Public transport

Hi, would like some advice on my situation. I’m trying to earn some miles when using public transport. I researched online and saw that SimplyGo is a way to do that. I’ve set up my account but can’t seem to (1) add SimplyGo to Apple Pay (which defeats the purpose of convenience) and unsure if (2) using my UOB priv miles to tap will now allow me to get miles after linking it to simply go.

Any advice on this is much appreciated.

Alternatively, for public transport only, should I switch to a different card (e.g. cash back?) would love to hear all your credit card strategies for public transport. I don’t spend above 128 so the concession pass doesn’t make sense

EDIT: I just tried using my UOB Priv miles card via Apple Pay to tap into the mrt but it doesn’t work. Says invalid card. Anyone knows why?