Sticky Geometry creating extra edges and face

Hi everyone,

I’m new here so I apologise if this is in the wrong place.

I’m following the Fundamentals tutorial, and while on the part about Sticky Geometry, I am encountering a problem

You see in the tutorial on the left, when merging the two faces, there is a clean edge. However, when I do this and move one face, there are new edges and a face created between the two (marked with arrow).

Why is this happening and how do I get it to stop? Thankyou in advance!

Can you post your model ?

It is difficult to diagnose the problem with only an image.