Substance painter not accepting on of my texture set

Hello everyone!
I've been adding new components and texture sets to my project. 
Everything worked fine except for on the new texture set: while it's supposed to be on UDIM 1001 and 1002, and has a mat ID on it, it does not show up as two different UDIM tiles in my texture set list. Actually, it does not even show as multiple UDIMs. I just added 5 new texture sets with the regular way of doing and only one didn't work.
Any clues why please? 
I'm joining some pictures so that you can have a better look at it! 
Thanks a lot in advance! 🙂