-Exit Bitcoin Core
-Backup your wallet.dat, even though you should have a backup already, make another backup
-Start Bitcoin Core from a command prompt with options -zapwallettxes -rescan (if you're using a pruned wallet, you can't use this)
Depending on your hardware, it will take a few hours to rescan. After this, your transactions should be gone, but Bitcoin Core might pick them up from mempool again. In that case just wait for it to drop again.
Full description of the commands:
Delete all wallet transactions and only recover those parts of the
blockchain through -rescan on startup (1 = keep tx meta data e.g.
account owner and payment request information, 2 = drop tx meta
data)
Rescan the block chain for missing wallet transactions on startup
Another tip: don't use inputs like this one:
One last thing:
You also own Bitcoin Cash, Bitcoin Gold and Bitcore! If you didn't know this yet: it's worth about $700 in total. After moving your Bitcoins, I can explain how to claim it if needed.