Via placement issues on simple DOE

hello, new user here working on a simple 3 layer layout to do rf tests for material selection. Essentially just two rf pads for test probes on top layer and a stripline signal connecting them on L2.

I am trying to do the via array placement along both sides of the trace. I have defined a padstack and BBVias L1toL2 and L2toL3. Would like to stagger these vias alternating along the trace. When I have the preview on and for placement and when I go to place, it doesn’t let me click them into place on the board. The only place it allows me to click them into place is if I click them onto the outside of the board, then there is a row inside/outside of the outline. I don’t have any keepouts defined in this layout. Any ideas on how I can resolve this issue? Is there something off in my constraint manager settings that won’t allow the placement along the trace?