I did a refund but the customer still sees the charge on their account.
The number of days it takes for your customer to see a charge drop off their account depends on how the return is processed.
If you run a reversal, it generally takes 2-3 Business days.
If you run a refund, it generally takes 3-5 business days for the customer to see the funds released.
If you void a transaction it can take 7-10 business days for the charge to drop off.
Keep in mind that Reversals and Voids can only be done prior to batching the terminal. If your customer reports that they have not seen a charge drop off and they are still in the time frame listed above you can encourage them to reach out to their issuing bank and see if the bank with release the funds early.