Problems with Android li4278 Bluetooth scanner

Helloo

 

I'm trying to connect this device with a cell phone that has android.

I have the following problems:

1- The connection is short and it is disconnected.

2- When you want to connect it again, it connects and disconnects instantly.

3- I have to reset the factory scanner and configure it again so that I can reconnect it and even then the connection continues to last a short time.

 

 

I have tried different cell phones of different brands and software versions (android).

 

 

I verified on the internet that the version of bluetooth that handles the scanner (2.1v class) was compatible with that of the cell phones (4.1 and 4.0)

 

 

Can you help me if this problem has already happened to you?

or do you know that the problem may turn out to be?

 

 

Thank you