encrypting dude

Hello, I am using truecrypt / veracrypt already for many years. had never problems until now. I know using hibernation is a huge security problem, please no discussion over this. Anyway, I m sometimes using it. Last time hibernation took very long so I just pressed on the power button (encrypted partitions were decrypted and mounted). I dont not unmount the veracrypt partitions explicitly. Then after restart 1 of all my encrypted partitions cant anymore decrypted/mounted, it says wrong device/password/keyfile/etc....