i really think i don't have a backup of that - i emptied that wallet while ago and few weeks ago i wanted to verify that balance is 0 and get rid of it so i don't have a dozens of empty wallets

i would never ever expect to loose any btc as i have backup, backup of backup, and backup of backup of backup in different places on multiple media

all it took is one wrong assumption on how software i have been using works and bang