Hi @manishie@gordonswaby
Answer is in a bug in Lastpass CLI
Here is basically the Github thread with the fix : https://github.com/lastpass/lastpass-cli/issues/604#issuecomment-844210600
Long story short :
A workaround is to:
1. Open `Account Settings` in your browser (`Open My Vault` → `Account Settings`)
2. Press `Show Advanced Settings`
3. Set `General → Security → Password Iterations` to *exactly* `100100`
LastPass will ask for your Master password and re-encrypt your vault. After that using `lpass` *should* work again.
It helped me, hopefully it will help you (and others) too