your colors are so pretty!
I would measure the width of the strips and restitch a few of them...the picture is hard to see which strips are the problem..pressing and spray starching using a straight guide line works sometimes too.. press sticks look like they would be great for keeping pressing from distortion...I always have a challenge with exact seams..BUT all of the suggestions are good! I know sometimes I feel like smashing them
hope you find a good solution!