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Just 3 characters, please what should I do?

Great, if only three characters are missing, we can figure this out.

1.) I can give you a Python script that finds the missing characters. All you’d have to do is enter your master password (missing characters marked with question marks) into the script and run it. That would be Option 1, if you’re able to do that—maybe because you’ve worked with Python before.

2.) If option 1 isn’t an option for you and you still have your private Memo Key, you could send me an encrypted message with your master password. Please mark the missing characters with a question mark (?) like this:
P5KEphVePyvwYuawtAUT4duTBRXkL24a3qwDroahcDx?tah?vs?g

I’ll then find the correct password and send it to you as an encrypted message; after that, you’ll need to change your password, of course.

Those are my ideas, but it might be easier with @alejos7ven if you’re connected via Telegram.