Keyfinder 4 not working

[_Swords_]

To get straight to the point my key finder 4 doesn't work, from my key finder 2 i get keys for every cca 30 blocks I mine and with key finder 4 i don't get any at all.
btw I got it from Unique crate.

 

[Stormidity]

Same happening here i bought actually and the key drops like any other pick

 

[Stormidity]

I reported it on bug reports hey should respond