I can't delete skins from the skin library

Hi! So I haven't played Minecraft for a super long time and I opened the launcher today to discover the skin library for the first time. I thought "oh cool!!", and decided to press the button to add my current skin to the library. However this didn't work properly, as the area where my skin should have been was blank, and it was titled <unnamed skin>.

I thought this was weird so I tried deleting it - this appeared to work at first, but upon closing the launcher and reopening it, the blank unnamed skin appeared again. I thought maybe this was happening because the skin was blank, so I clicked on the skin to edit it and uploaded my skin's file over it and gave it a name. Then I tried deleting it again, but again, upon closing and reopening the launcher, the skin was still there (though this time it still had the name and skin I'd uploaded onto it).

Does anyone know why this is happening?

Thank you!!