If you're experiencing issues with multi-touch or trackpad functionality in landscape mode on your 2019 MacBook Pro, there are a few additional troubleshooting steps you can try:
1. Check for debris: Make sure the trackpad is clean and free of debris, as this can affect multi-touch functionality.
2. Adjust trackpad settings: Go to System Preferences > Trackpad and adjust the settings to see if it resolves the issue.
3. Reset the trackpad: Try resetting the trackpad by clicking the "Reset" button at the bottom of the Trackpad preferences window.
4. Update macOS: Ensure your operating system is up-to-date, as updates often include bug fixes that may address trackpad issues.
5. Disable and re-enable the trackpad: Go to System Preferences > Trackpad and toggle off the trackpad, then wait a few seconds and toggle it back on.
6. Boot in Safe Mode: Restart your Mac in Safe Mode (hold the Shift key while booting) to see if the issue persists. If it doesn't, it could indicate a software issue.
7. Contact Apple support: If none of the above steps resolve the issue, it may be a hardware problem, and you should contact Apple support or visit an Apple Store for further assistance.
Let me know if you need more help or have any other questions!