Had a similar issue - my SD forced listing sold and a label fee was charged automatically, even though I didn't require it (sold item was being posted along with another non-SD item to the same buyer). After 1hr 30m I was eventually pointed towards a 'Request a refund for Simple Delivery' page where it states a refund will take up to 14 days!!!
Another way for them to keep your money in their account earning them interest I guess is the thinking. 🤔  The same as many others, my sales have fallen through the floor after their daft Seller Protection Fee .. and this is just driving home the nail in the coffin.