A monthly subscription I pay out of a different bank account has started to appear on my Monzo account . Why is this ? I have not agreed it ?
The only reason this could have happened is if you gave the company your monzo details or did a current account switch
Subscriptions can’t change the bank they are taken from by magic, some action must have been performed by you to provide them with the Monzo bank account/card details.
Do you pay it with Paypal or Google/Apple pay? Changing the card details on those services could make it come out of a different account.
Monzo can’t go to whatever supplier and say hey we’ve seen one of our customers is using a competitors account with you. Please change it to ours.
As others have said, something you’ve done has updated the details for whatever the subscription is.
If this is related to Apple and you have both cards registered, they will take from top down.