I have two pieces of knit one purl one fabric that need a seamless join.

A kitchener for ribbing? Don’t know how to do it!

Same number of stitches and stitches are live on both needles.

Three needle bind off will have ridge.

Needs to be seamless. I made a mistake and am trying to rectify it!

ANY help would be most welcome!!!

What is it you’re making? Without knowing what you’re doing it’s hard to tell you exactly. Since you have live stitches kitchener would probably work, but since it’s k1, p1 it’ll be a little trickier.

There are some seaming techniques here in KH -

And here if you scroll down to finishing techniques