Frostbite765

I i just got Apex 2 days ago and I wanted to make a mission. So I started to make it. Everything was fun until I changing the respawn setting in attributes. When I clicked on respawn and the selections came down, I couldint click on any of the selections, I tried everything but I couldint click on it. This also was a problem with other selections that work in the same way. Please tell me how to fix this, thank you.