Scalar Value As An Array Problem

HI there

I am getting a ton of failed subscription notifications which all read:

09-14-2023 @ 07:24:27 – scheduled action 464254 (subscription payment) failed to finish processing due to the following exception: Cannot use a scalar value as an array 09-14-2023 @ 07:24:27 – action args: subscription_id: 33433

Which isn’t helpful at all unfortunately. I don’t know why its suddenly failing these subscriptions but it seems like its something to do with WC Payfast, the other payment provider isn’t showing any problems. There is also no note unfortunately in the order which details any more details about the issue.