Merchants taking unauthorised payments

I took a cab to the hospital and back - paid via Apple the two payments went through my bank account two days later.

the night after I ordered a cab - it didn’t turn up.

another cab (same company) was passing so we grabbed that and paid by cash.

the following day two payments were taken by Airpay (Apple)

investigation will be underway - but how do I stop unauthorised payments being taken in this way - I didn’t double click or follow a link at all - so this has to be theft.