Game says Entei is not registered… but I have it?

I completeled my first remote trade today, but noticed in their Tag, their Enteis tagged said I didnt have them registered. Im curious as to why. You can see my personal Entei inventory that I do have it. This was the only Legendary I noticed that did this that I didnt have. I also tried searching their inventory for XXL and XXS to see if this is why and nothing came up.