One possible explanation for this behavior could be related to the region settings on your device and how they interact with Wi-Fi networks in different countries.
When you travel to another country and restart your phone, it may attempt to adjust its settings to comply with local regulations or network standards. This adjustment could potentially cause issues with your Wi-Fi settings, such as turning off Wi-Fi or changing the hotspot password.
To address this issue, you can try a few troubleshooting steps:
1. Go to Settings > General > Reset > Reset Network Settings. This will reset all network settings, including Wi-Fi passwords and VPN configurations. After resetting, reconnect to your Wi-Fi network and see if the issue persists.
2. Ensure that your iPhone's region settings are correctly set to your current location. Go to Settings > General > Language & Region and verify that the correct country or region is selected.
3. Make sure your iPhone is running the latest version of iOS. Sometimes, software updates contain bug fixes and improvements that can resolve issues with Wi-Fi connectivity and settings.
4. If the issue persists after trying the above steps, consider reaching out to Official Apple Support for further assistance. They may be able to provide additional troubleshooting steps or advise you on any potential hardware issues.
It's also worth noting that using a VPN or certain security features on your device may affect how Wi-Fi networks are detected and connected to, so you may want to review any settings related to network security or privacy.