How do I connect to the LTS21 with an IOS phone quickly?

①Turn on the Headphone Notifications in the phone's settings. (Sounds & Haptics---Headphone Safety---Headphone Notifications)
②Turn on the Bluetooth of the phone. Press each ear device for 3 seconds to activate it and turn on your phone’s Bluetooth. 
③Select our headphones device name in the Bluetooth interface. The mobile phone will connect to it automatically.