Device Type: Bluetooth Headphones (with microphone in each earpiece)
Type: inserts
Type: Dynamic
Frequency range: 20-20000 Hz
Impedance: 32 ohms

Battery capacity
Headphones:
QCY QS1 (T1C) / QCY QS2 (T1S) - 43 mAh
Charging box:
QCY QS1 (T1C) - 380 mAh
QCY QS2 (T1S) - 800 mAh

Design
Fastening type: without fastening
Headphone weight: 4.3 g
Indication: red-white LED work on headphones
Headphone / case charge display: no
Key on earpiece: mechanical

Wireless connection
Bluetooth support: Bluetooth 5.0
Profile Support: A2DP, AVRCP, Hands free, Headset
Range: 10 m

9 out of 10 problems with disconnect, split sound and other malfunctions are treated FULL RESET headphone to factory settings.

Please, before creating a comment with the question “What should I do ?!”, perform the simple actions listed below. And even if they did not help, in a comment asking for help, start with "I tried a full reset" .
Respect other users, the topic is heavily cluttered with variations of the same “problem”.

(Note: with just unpacked headphones, you can start immediately from point # 6)

CAREFULLY do:
1) In the phone go to Settings - Bluetooth. In the list of paired devices, we cancel the pairing of the right and then the left headphones first, thus removing them from the phone.
2) Turn off the Bluetooth on the phone.
3) Turn off the headphones by simultaneously pressing their buttons for 3-4 seconds, the descending signal sounds, they turn off.
4) We take both headphones in our hands, simultaneously press the buttons and holduntil the arm gets tiredlonger than 20 seconds, and in order to be sure, 40 is better. During this time, one after another, several things happen - unplugging the headphones from each other and FULLY reset them. During these 40 seconds, three series of flashes of different duration will occur, it is not necessary to consider them, all that is required is to hold the buttons firmly. Even if it seems that everything is already blinked. Just 40 seconds hold.

5) After resetting, put the headphones in the box.

Pairing headphones with each other:
6) Headphones in the box, if the red lights are off, right there, press and hold their buttons for a couple of seconds until they light up.
7) We take the headphones out of the box, keep them close, the headphones mate with each other AUTOMATICALLY, they do not need help.

Connect to the phone:
8) We return both headphones to the box.
9) On the phoneturn off Wi-Fi , on some phones it interferes with the connection, may interfere with the first connection.
10) Go to Settings - Bluetooth and immediately get the RIGHT earphone from the base, the left one remains in the base. If you miss, the search for Bluetooth stops after 10 seconds, start it again by clicking on “Refresh” below.
11) The phone's Bluetooth detects the right earpiece and asks for permissions. We give access and permissions, the earpiece moves above, to the list of attached devices.
12) We put the right earbud in the ear. We take out the left earpiece from the box, it automatically connects to the right one.

If you want to use the left earpiece separately, when the right one is in the database, you need to bind it so that it also appears in the list of devices. Also, as a result of working in pairs, the right earpiece sits faster than the left one, so an autonomous left one can add from half an hour to an hour to listening.

To connect the left:
13) We put both headphones in the box. We reach the left, turn on the search for Bluetooth on the phone. The phone doesn’t find the left earpiece right away; you may need several approaches and pressing the headphone button, updating the Bluetooth search. Finally there is a proposal for pairing, give access and permissions.
Now you can nominally get the right from the box, then the left and listen to them in the stereo pair, and you can also separately listen to the left when the right is in the base.


Connect to the phone:
Instruction