Why can't i place this spymaster next to one garrison but I can another?

https://ibb.co/0pQT0CbF

here's a link to my temple I'm building for a new character. The square with the red x (next to the last link in my chain which is a garrison) won't let me place a spymaster or an armory there and I don't know why....

Anyone know why I can place the spymaster at the end of the bottom (the blue square I circled) but not the red one?

thanks in advance?

because you have a commander in your chain and cannot place anymore spymaster on your chain past that point.

ooff....thanks. guess ill let it dissipate and get rid of the commander...thanks..