@pastelpetals123 - Exciting to hear that you have these goals!
So you "think" it's because of your measurements. Before you proceed with any changes/decisions based on this hypothesis, can you ask the companies/representatives why you got rejected? There's no harm in asking. And who knows, it might open a door for future opportunities based on your persistance and interest in the industry.
Second, be prepared for the answer. What IF they do say that they're looking for a model with different measurements. Prepare yourself mentally for the consequences of that. Would you be prepared to change your physical makeup to make that happen? There are pressures when we have to keep our human machines in a set ratio of proportions and lots of variables that we don't have a lot of control over...calories in vs. spent doesn't always equal the proportions/body we were intending to create. Our minds then can become obsessive if we stray outside of the measurements. Can lead to anxiety, anger, sadness, frustration...even worse, poor health and nutrition and mental challenges and onward. Look inside and see if you're prepared to keep yourself in check and mentally healthy to stay within healthy thinking.
With those things in mind, will it be worth it? Does modeling/the thought and possibility of it bring you joy? If yes then proceed with your decisions, holding onto that ultimate goal of joy for what you're doing.
Best of luck.