US Polo Assoc NWT long sleeve t-shirt with gray stripes, Large but runs small

This is a US POLO Assoc long sleeve t-shirt. It has gray stripes and some glitter stripes too that are hard to see in the pictures. It is listed as a size Large but when I tried it on, it didn’t really fit well in the arms. The measurements of pit to pit and length are shown in the pictures. The shirt is coming from a pet free and a smoke free home. Please ask questions!