The -resyn went on smoothly until it is stuck at 'Downloading headers.. 6 days behind'. It has been 6 hours since it stuck there. The debug log says:
Upload your debug.log file to mega or something so we can take a look at it.
Thanks for the offer to help. I succeeded in restoring my wallet by deleting everything (but first backup the wallet) and then replace the newly generated wallet with my backup wallet. The blocks are newly downloaded.