Probably an easy fix but I am getting aggravated.

so in this example, I have 2x2ft concrete tiles that I am laying out on a marina I have designed. So I linear pattern on the X axis, then I select that row and linear pattern it on the Y axis. yay!! streamers, and cake and such. HOWEVER (grumble), lets say I take a piece of 2x6in perimeter board and go to mate it to these tiles. For some reason, those pieces decide they are not fixed anymore and I get tiles ALL. OVER. THE. PLACE. Ctrl+Z multiple times and dissolve and fix seem to be a.... work around... but its not ideal. Should not linear parts be fixed? like... all of them?