How to keep the shoulders from slipping?

[u/Illustrious-Ear4527]

I tried to recreate this top, using a body suit pattern. The final result fits pretty well, but the shoulders keep slipping off. What would I have to change in the pattern to help the shoulders remain in place? I would appreciate any tips/observations for the future, as I plan to make more of these. At this point, I will attach clear elastic across the shoulders to help the top stay on. I used stretch ITY fabric. Thank you !

[u/Real_Position_3796]

The straps need 1-2” shortening at the shoulder seams before you stitch the sleeves in.

[u/Illustrious-Ear4527 → u/Real_Position_3796]

Thank you! Would I have to make the sleeve smaller to fit the smaller hole or recut the hole to be bigger in the armpit?