Your micro SD card is dead. It could have been killed by over-writing (ie, swap) or heat, or simply by failure. The card should not be used again for data.
There is some small chance you can recover data by putting the card into a reader and another device that understands the filesystems, so a linux desktop.
For completeness, here are the kernel messages in dmesg
when the card is trash.
kernel: usb 4-1.6: new high-speed USB device number 37 using ehci-pci
kernel: usb 4-1.6: New USB device found, idVendor=1908, idProduct=0226
kernel: usb 4-1.6: New USB device strings: Mfr=0, Product=0, SerialNumber=0
kernel: usb-storage 4-1.6:1.0: USB Mass Storage device detected
kernel: scsi host6: usb-storage 4-1.6:1.0
mtp-probe: bus 4, device 37: "/sys/devices/pci0000:00/0000:00:1d.0/usb4/4-1/4-1.6"
mtp-probe: 4, device: 37 was not an MTP device
kernel: scsi 6:0:0:0: Direct-Access Generic Mass-Storage 1.11 PQ: 0 ANSI: 2
kernel: sd 6:0:0:0: Attached scsi generic sg2 type 0
kernel: sd 6:0:0:0: [sdc] 30449664 512-byte logical blocks: (15.6 GB/14.5 GiB)
kernel: sd 6:0:0:0: [sdc] Write Protect is off
kernel: sd 6:0:0:0: [sdc] Mode Sense: 03 00 00 00
kernel: sd 6:0:0:0: [sdc] No Caching mode page found
kernel: sd 6:0:0:0: [sdc] Assuming drive cache: write through
kernel: sdc: sdc1 sdc2
kernel: sd 6:0:0:0: [sdc] Attached SCSI removable disk
kernel: usb 4-1.6: reset high-speed USB device number 37 using ehci-pci
kernel: usb 4-1.6: reset high-speed USB device number 37 using ehci-pci
kernel: sd 6:0:0:0: Device offlined - not ready after error recovery
kernel: sd 6:0:0:0: [sdc] tag#0 FAILED Result: hostbyte=DID_ABORT driverbyte=DRIVER_OK
kernel: sd 6:0:0:0: [sdc] tag#0 CDB: Write(10) 2a 00 00 88 20 08 00 00
kernel: blk_update_request: I/O error, dev sdc, sector 8921096
kernel: Buffer I/O error on dev sdc2, logical block 1048577, lost async page write
kernel: sd 6:0:0:0: rejecting I/O to offline device
kernel: sd 6:0:0:0: killing request
kernel: sd 6:0:0:0: [sdc] killing request
kernel: sd 6:0:0:0: rejecting I/O to offline device
kernel: sd 6:0:0:0: rejecting I/O to offline device
kernel: sd 6:0:0:0: rejecting I/O to offline device
kernel: sd 6:0:0:0: [sdc] FAILED Result: hostbyte=DID_NO_CONNECT driverbyte=DRIVER_OK
kernel: sd 6:0:0:0: [sdc] CDB: Write(10) 2a 00 00 88 20 80 00 00 08
kernel: blk_update_request: I/O error, dev sdc, sector 8921216
kernel: Buffer I/O error on dev sdc2, logical block 1048592, lost async page write
kernel: JBD2: recovery failed
kernel: EXT4-fs (sdc2): error loading journal