Do you mean how to remove the postal charge?
If you are now changing to a collected item you will not receive that all important collection code which when scanned is your only proof the item has been collected.
Best way forward is to cancel the order citing Buyer requests to cancel. This refunds the buyer and your seller performance is not affected. Then relist the item as collection only. That way, buyer receives that 6 digit collection code they must give to you on collection, it's advisable not to let the item go without receiving the code.
You will need to message the buyer you are going to do the above, but make it very, very clear in your messages as eBay do read all messages going through their system, that the item will be relisted on eBay again for the buyer to buy , that this is Not an off eBay sale. !
@welsh24
