Yes, first try to enter recovery mode, if it doesn't help, do as here:
https://www.mobileread.com/forums/sh...5&postcount=23
When you remove the back cover you will see a sticker with the serial number, usually it is located on the Akku, but it can be in another place. The serial number has 8 characters and starts with 23......
Also, if you create your own image from a "defective" SD card, you will find your serial number as I wrote above using HxD Editor.
How to remove SD card see these topics about Kobo Libra 2, it may be useful:
https://www.mobileread.com/forums/sh...d.php?t=348546
https://www.mobileread.com/forums/sh...43#post4166043
https://www.mobileread.com/forums/sh...22#post4213922
And this:
https://www.ifixit.com/Guide/Tolino+...Upgrade/168276
https://mega.nz/file/7ls1VTZB#cdfVw7...N4T645P9R9ljgk
https://mega.nz/file/nhUmHQqZ#rI9X17...pJgb7BWM29_fK4
https://mega.nz/file/W5NxDKAR#yb4P7C...lyNdY3xfHIOjy8