To rectify or "boost" your network signal, you can:
Step 1. Restart the device.
Step 2. Activate then deactivate airplane mode
Step 3. Confirm the device’s network capability by going into Network Settings. Some devices only facilitate 2G/3G connection.
You can switch between connections, for example, from 4G LTE to 3G or 3G to GSM only. Ensure a restart is done once any adjustment is made.