Under Armour Men's HeatGear Compression Short-Sleeve T-Shirt

So earlier this year, I bought another one of these in burgundy, and loved it, so I figured I should get myself another one! And, well. It's good but, it runs noticeably smaller. I even tried them on back to back, and double checked it was the same size and yeah, it feels smaller around the armpits and in the overall length. Even checked the tag and the materials used actually changed, so that may play a part in it. Overall, it's fine, just disappointed. Really hope it's not a change in all of them and just happens to be a change in this colour in particular.Additionally, when I purchased this, I chose the 4XLBig but was later told by the seller that it was a mistake, as they simply sell 1 standard style. Hoping this gets changed at some point as I was told.