I'm sorry to hear that you're having trouble signing in to your account. Could you please share a screenshot of the error message you receive when attempting to sign in? Make sure to hide any personal or sensitive information before sharing it. This will help me better understand the issue and guide you toward the appropriate solution.
Additionally, if you haven't already, I recommend trying Microsoft's Sign-in Helper:
This tool is often very effective at identifying the cause of sign-in issues and providing the appropriate next steps. I look forward to your response to continue troubleshooting.