Hello! I understand you're having trouble logging into the Readoo app after uninstalling it, and it's showing "visitor login failed." Let’s try to get this sorted out together.

First, just to make sure, could you tell me:
- Are you trying to log in with a visitor/guest account or with your regular user credentials?
- Have you tried logging in with any other method (like an email or social login)?
- Also, do you recall if your device’s Android System WebView is up to date? This component impacts app logins on Android 10 quite a bit.

Meanwhile, here’s a simple step-by-step guide to try:

1. Check Android System WebView:
- Go to the Google Play Store on your device.
- Search for "Android System WebView."
- If there's an "Update" button, tap it to update. If it's disabled, enable it.
This process helps apps handle web content properly, including login screens.

2. Clear app cache and data:
- Go to your device Settings > Apps > Readoo.
- Tap on Storage.
- Clear Cache first, then Clear Data.
- Open the app again and try logging in.

3. Reboot your device:
Sometimes a simple restart helps clear temporary glitches.

4. Reinstall the app:
Since you already uninstalled it once, try reinstalling the latest version from the Play Store to ensure you have the newest build.

If after these steps the visitor login still fails, it might be related to server-side issues or tokens associated with visitor sessions that don't persist after uninstalling. Usually, logging in with a registered account would avoid that.

Could you try these steps and let me know what happens? If it still doesn’t work, we can dig deeper!