For your reference, there is some information for this problem as below:
1. In outdoors with cold weather, touching the earbuds will cause them to malfunction when hands become dry;
2. When the earbuds are not worn, to avoid accidental contact, pressing the touch control area of the earbuds will not take effect;
3. For the touch area and operation method of earbuds, it is necessary to tap on the touch area indicated by the User manual of the earbuds. If the tapping is not in the designated area or the continuous tapping interval is insufficient/the tapping force is not enough, it will cause the tapping touch area to have no function.
4. Fingers are dirty or have too much liquid, causing the pressing touch control area to be insensitive.