I would be concernned too if I couldn't connect to Wi-Fi networks with my iPhone, especially in locations where others can. I recommend reviewing the article below and specifically the steps from the following section:
Unable to connect to a Wi-Fi network
- Verify that you are attempting to connect your desired Wi-Fi network.
- Make sure you are entering your Wi-Fi password correctly.
- Passwords may be case sensitive and may contain numbers or special characters.
- Reset network settings by tapping Settings > General > Reset > Reset Network Settings.
- Note: This will reset all network settings including: previously connected Wi-Fi networks and passwords, recently used Bluetooth accessories, VPN and APN settings.
You can find the full article here:
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