Cannot connect bluetooth keyboard

Hello,

I have Sony XA2 and Sailfish OS 3.4.0.24. I am trying to connect bluetooth keyboard Evolveo WK29B.
Good thing is keyboard is found by the Sailfish.
Bad thing is I am not able to pair it or I do not know how to do it.
When I want to pair the keyboard, it is asking me for pass-code. You can see screenshot. Where should I take pass code from ?
If I enter any pass-code, it immediately response with error message that pairing failed.

When I tried to pair the keyboard with tablet, I saw the pin on tablet, which I entered and keyboard was paired.

Any ideas ?

Thanks a lot

0000
1234

You saw which code where to enter it where?

To the tablet scenario:
I saw the pin code on the tablet, when I was trying to pair the keyboard.
And then I typed the pin code to the keyboard and press enter. Then it was paired.

With Sailfish OS I see no pin code, but it is asking about some. If I enter any (like 0000, or 1234) it responses with the message the pairing fails.

Sounds strange.
What was the password? Was it like an autogenerated one when you pair like a smart phone with another one or a PC? Or a fixed one (did you try this one as well?)
Because normally such devices like keyboard or sound speaker use a simple fixed password…