Why does 'undefined method source for nil:NilClass' appear in multibank payments?

[kittyoasis]

Hey, do you now why this appears when people try to use the multibank? undefined method `source' for nil:NilClass

[kittyoasis]

Hello, thanks for the reply, i have shopify payments. My store link is kittyoasishop.com

[kittyoasis]

It's a new store but yes, Im doing Facebook ads and posting there, YouTube not so much