shift kit problems

New performance trans with shift kit but not getting the results still. felt like stock trans shifted harder or better

Welcome to AF
Always give year and engine and transmission and mileage when you post.
And all of the info you can.
What kind of shift kit was it?
What is it doing or not doing?
MT

Tell us more about the rebuilt transmission?
Any warranty on the rebuild?
Have you taken it back and asked them to check it out?
Was the kit added at the time of rebuild?
Are you getting any transmission codes?
What transmission and what kind of a shift kit?