Hello HM-Bookkeeper-UK thanks for posting on the Community page, so Error - 81624 is normally this Something's not quite right. Please update your payment information and try again. If the issue persists, please contact support and reference this message (Error code:-81624) is from payment authorisation failed.
You the customer will need to either use a different credit card or contact their Financial institution to understand why they are not relinquishing the funds.
If you are getting something else with that code then we would advise you ring the supportline on 0808 234 5337 so you can set up a screenshare with the agent on the phone so this can get looked into more for you.
