Apple Pay not working 'this website was not able to complete the payment'

[Vij95]

My customers have been receiving this error when trying to make a payment using Apple Pay.

I've tried making payments myself through my website using Apple Pay and keep getting the same error as well. I tried on both my iPhone and iPad.

Any suggestions on how to fix this? 

[ruth123]

I'm having the same issue and i'm using the Shopify payment