Formatting should only take a minute at most - if that!
The format process is not low level, hence data on the card is not deleted - its just marked as overwritable - so this should only take a few seconds irrespective of the card capacity : certainly not hours (that is what I would expect for a low level format where all data is zero'd out).
Do you have a lower capacity card you can just use to test?? Could be that you have a clone card, hence why the errors when formatting - with clone cards the capacity can be read as 256GB or 1TB, but when the system tries to format to use that capacity, it cant find the memory cells, and hence errors.....
The format process is not low level, hence data on the card is not deleted - its just marked as overwritable - so this should only take a few seconds irrespective of the card capacity : certainly not hours (that is what I would expect for a low level format where all data is zero'd out).
Do you have a lower capacity card you can just use to test?? Could be that you have a clone card, hence why the errors when formatting - with clone cards the capacity can be read as 256GB or 1TB, but when the system tries to format to use that capacity, it cant find the memory cells, and hence errors.....