Created a fillable PDF form on my PC, customer with Mac is having issues with the fillable fields not working properly.

I created a fillable PDF form on my PC, my customer with a Mac is having issues with the fillable fields not working properly. Do I need to create the Fillable form on a Mac in order for a Mac user to use my form properly? Is there a different process to create a fillable form in Mac vs. PC? She's not getting check marks when she checks off the boxes, instead she's getting smaller boxes, fillable text boxes disappear completely, some of the fillable check boxes are also off alignment. How can I fix this?  Thanks