Hi there! I understand you're having trouble logging into the Fifth Third app after multiple attempts. I'd be happy to help you get this sorted out.

To start, could you let me know if you're seeing any specific error messages when trying to log in? Also, have you tried resetting your password or user ID yet? This info helps me guide you better.

Meanwhile, here’s a step-by-step approach you can try on your Mac running OS X 10.15.7:

1. Check Your Credentials: Double-check your user ID and password for typos or capitalization errors since those are common login hiccups.

2. Reset Your Password: On the login screen of the Fifth Third app or website, click "Forgot Login" or "Forgot ID or Password?" then follow the prompts to reset. This often resolves issues related to forgotten or mistyped login info.

3. Clear Browser Cache and Cookies: Since you’re on a Mac, open Safari (or your preferred browser), go to Preferences > Privacy > Manage Website Data, then remove any data associated with Fifth Third. This can fix session or cookie-related problems.

4. Restart Your Device: Sometimes a simple restart clears temporary glitches.

5. Update or Reinstall the App: If you're using the Fifth Third app on your Mac, make sure it’s updated to the latest version. You can delete and reinstall it from the App Store to ensure a fresh start.

6. Check for Account Lockout: Multiple failed attempts could temporarily lock your login for security. If you see messages about being locked out, it might be best to wait 15-30 minutes or contact Fifth Third’s customer support to verify your account status.

If you’ve tried these already or there’s a different issue, please tell me what’s happening when you try to log in, and I can guide you through more advanced troubleshooting.

Are you comfortable trying these steps now?