"There is, however, a less well-known fact: the tab is implemented only as mechanical part (detected by a contact switch inside the SD Card socket) so that the device can write to the write protected SD card if its firmware decides to ignore the tab or if the switch is broken. Many users reported data loss when the switch was worn down or broken especially on early sockets where manufacturing process was not perfected or due to firmware bugs. Some devices also allow users to ignore write protect switch for user's comfort."
I don't have your card to examine but it shows that write protection is not in the card but a function of the host device. So this leads us to try another host device or replace the card to see if the card has failed.
I won't look into your user manual to see if your device can format a card. I leave that to you.
Bob

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