Shirt size

I have ordered about 15 tshirts over the last 2 years and I love how they turn out , however when I order the shirts they keep switching up their brand of t shirt. When I get an xl sticker Mule brand shirt it fits perfect but then sometimes they send me another xl brand and the shirt is way to big to ware so I just wasted my money then I wish they only sold the sticker Mule brand t shirts.