Unable to read memory card. Reinsert memory card.

When inserting the memory card i get the error mentioned above. I can insert the sd-card fully. It seems to be clean on the inside. What i tried so far:

• Various cards (128MB, 8GB, 12GB, 64GB) and they all work on computer
• remove every partition on the computer from the card and i formatted it with FAT32
• I followed this video https://www.youtube.com/watch?v=c6rLkdxn... without success.
• Cleaned the Slot with some paper around the sd-card
• Some mystical ‘hard reset’ via https://us.community.sony.com/s/question... or https://www.dpreview.com/forums/thread/4...
• Haven’t followed https://www.youtube.com/watch?v=DInReh7R... so far as it seems to be a solution if there is something stuck and thats not the case here.
• Update Firmware: Not possible as the cam is already on the newest firmware.

I’m asking myself if a replacement of the sd-card-slot is the only viable solution and if anybody knows the part-number of this thing so i might be able to order it somewhere?