Question Bluetooth App not pairing - PIN refused

[colettina]

I am not sure, whether this is the right category in this forum, but I have chosen this, because the Bluetooth pairing problem is happening on my android smartphone, when I want to connect it to a Bluetooth controlled camera slider, produced by Neewer. In their manual, they do not mention any PIN code and thus any connection request is refused.
The device (camera slider) is detected by my smartphone immediately. A Bluetooth connect can be established for pairing purpose, because the blinking of LED while waiting for connection stops blinking and stays on, while I have to fill in the PIN in the form. When I Click OK after having tried the default PIN like 0000 or 1234, the connection is refused, telling that the PIN is not correct.
Further I can select an option in the form, which will allow to access all contacts on my phone. Even when I give access, the connect will not establish.

Additional information: From datasheet, I know, that the slider Bluetooth control as well as my smartphone both do operate with Bluetooth v4.0 – During my efforts, to get pairing, the distance between the devices was only some centimeters and no other Bluetooth device was connected to my smartphone in this time. Further I am sure, there was no additional RF interference from other transmitters at this time. I cannot find the manufacturer in the web and do not have a service address. The product has been sold via amazon, but by an unknown seller, who is not available any more after the deal.
How can I overcome these difficulties and get pairing?

 

[Sagar_20]

There must be some pin code in the user manual or on the back of that device. Look for it. 0000 or 1234 can possibly work depending on how many digits it's asking for. Also, as long as it bt 4 or later, connectivity shouldn't be a problem at all. I'm able to use my bt 4 headphone from as long as 10 metres from my phone, sitting in another room, with multiple obstacles in between. If you have no clue what's wrong, go to the page from where you bought it and check customers feedback. Search for the keyword you think is causing the problem.

Your phone shouldn't be even asking for a PIN, unless you are transferring data between devices as that process requires authentication.

 

[colettina]

As you can see, I have already tried out, what you do suggest. In the meantime, I had intense contact to the support of the manufacturer, but they could not help me either. They told me, that their App would do the pairing automatically and that I should not try to pair via the settings / bluetooth menu of the smartphone.
I have given up and returned the camera slider now.
There is one thought left: Perhaps the App could not pair because it is no "normal" Android system running on my smartphone but LineageOS, so that LineageOS perhaps handles bluetooth pairing on other way, than "original" Google Android?