Issue when connect Macbook Air to Logitech keyboard via bluetooth

I can not connect my Macbook Air to the Logitech K375s.

I followed the guide attached with the production. The connection lost after 5s and the status of the connection is "not connected". I tried many times but received the same result.

I connected successfully to my Iphone. When using the Unifying receiver, the connection runs smoothly. It means that the trouble is from my Macbook.

Could anyone give me the advice to fix this issue?