Due to platform-related behavior on iOS, this issue can sometimes occur. Please try the following steps to resolve it:
1. Open the Settings on your iPhone and go to the Bluetooth menu. If the speaker appears in the list of previously connected devices, tap the “i” icon next to it, then select “Forget This Device.”
2. Follow the pairing process again and connect to Bluetooth, then re-open the Nothing X app to search and connect again.