Hot spot

Please see the pic below to make it clearer that Hotspot is enabled by a Carrier on one SIM and not by the other Carrier in the same iPhone (Dual SIM).

Use these steps first

Restart the iPhone or iPad that provides Personal Hotspot and the other device that needs to connect to Personal Hotspot. Make sure that you have the latest version of iOS. On the iPhone or iPad that provides Personal Hotspot, go to Settings > General > Reset, then tap Reset Network Settings.

If Personal Hotspot is not working on your iPhone or iPad (Wi-Fi

Also, check the following

1. Network coverage and stability
2. Data Balance
3. On your windows (See if WiFi Auto Joins is enabled)
4. Also, check if you have any stronger WiFi signal around your computer.

Ask the Carrier to change the SIM if nothing works.

There can be several reasons why you might be having trouble connecting your iPhone to a public Wi-Fi network. Here are some common issues and their possible solutions:

1. Many public Wi-Fi networks use a captive portal, which is a web page that requires you to sign in or accept terms and conditions before gaining access to the internet. When connecting to a public Wi-Fi network, open a web browser and try to access any website. If the captive portal page doesn't automatically appear, you may need to manually enter the captive portal's address or follow any instructions provided.
2. Make sure you are within range of the public Wi-Fi network. If you're too far away, the signal strength might be weak, causing connection issues. Try moving closer to the Wi-Fi hotspot to improve the signal strength.
3. Public Wi-Fi networks can sometimes become overloaded with too many users, which can result in slow or unreliable connections. If the network is congested, you may experience difficulties connecting or maintaining a stable connection. In such cases, consider connecting to a different network or trying again later when the network usage is lower.
4. Double-check that you are entering the correct password for the public Wi-Fi network. If you're unsure, try asking someone from the location or establishment offering the Wi-Fi for the correct password.
5. Public Wi-Fi networks often have certain security measures in place, such as requiring a VPN connection or specific security protocols. Ensure that your iPhone's settings match the requirements of the network you're trying to connect to. For example, some networks may require WPA2 or WPA3 security, while others may only support older protocols like WEP.
6. Sometimes, the problem may lie with the Wi-Fi network itself. It could be experiencing technical difficulties, such as router malfunctions or network outages. In such cases, there isn't much you can do except wait for the network to be restored or try connecting to a different network.

If you've tried the above steps and are still unable to connect, it may be helpful to contact the network administrator or the establishment providing the public Wi-Fi for further assistance.

To improve understanding of the phenomenon, it would be highly beneficial if you could share a screenshot. Visual representations carry greater impact than written descriptions.

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With the limited information that you have provided, It is hard to even guess the problems faced by you. 

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