What to do if the headpiece of the necklace does not return to the button after assembly?

The Xiaomi Smart Band 8 band supports quick release. The quick release button is a movable part. To prevent the head from shaking after assembly, the head is designed to be tight and has a buffer silicone ring. If the button does not rebound in place after assembly, you need to quickly press and tighten the assembly when assembling the strap to ensure that the head is assembled in place and the button can rebound in place.