Hello @HGSykes,
Welcome to the Klaviyo Community!
If your account gets suspended for a missed payment or we’re unable to charge the card you have on file, our system will automatically retry charging the card several times. This includes if you’ve updated the card on file as well.
In the event that you’ve updated your card on file and your account is still suspended after a couple of hours, I would suggest reaching out to our wonderful Support colleagues. They’ll be able to investigate the issue further.
From my experience, sometimes you may also want to check with your credit card issuer to make sure the payment isn’t being blocked on their end as a suspicious activity for security purposes.
I hope this helps!
David