It’s currently possible for the weekly region restrictions in PVP to be a duplicate of the previous week.
This is expected behaviour (not a bug).
We know getting a 2nd week with the same restrictions may not be as fun sometimes, but the intention is how the restrictions are chosen will be changed later as part of the overall plan for pvp, as there are more changes coming to PVP in the future to give it more depth and make it more engaging.