Have you tried contacting the author of the pattern? They should be able to help you locate where you might have gone wrong.
Generally speaking (without knowing the pattern):
Have you checked if your rounds have the number of stitches indicated in the pattern?
When it's getting wavy, it usually means that you have too many stitches in the round.
To help you keep track of the beginning /end of your round you might find it useful to use some kKind of marker like a stitch marker, safety pin or piece the yarn in a different color.
I hope you'll find the mistake soon and can keep enjoying the pattern.