The only links that can expire are recurring payment links. Banks require at least 48 business hours in order to set up recurring payments.
If you click on a recurring payment link and it says that it has expired, a new recurring payment link will need to be created. Please reach out to the company that invoiced you and ask for a new payment link to be created.
Once you have successfully set up the standing order from the payment link, you will not have to confirm the payment again. The money will automatically be taken out of your account on the set date.