I have owned three of those devices mate, first one wouldn't work, second one did for about two months & third one blew up my BC around 2.7bar.
I made several post like yours & got lots of advice about what I was doing wrong!!
It seems to me these things are not very consistent with some working for some & not for others.
PS I did write a long reply with links etc but got timed out, or lost the page somehow...