Can i go back to finish low level contracts?

I finished Rise of Kingdoms 16lv contract and got gems. But i didn't enter other low levels contracts such as 15lv, 10lv, tutorial. Is it possible to go back finish it? And i wonder if i start with tutorial contract, then 10lv, 15lv, 16lv. I can take all gems? Or i can only choose one contract?

im trying that too rn i hope it works but idk

no its not working for me

Pretty sure that won't work

You can only choose one contract for that certain task, you can see: "For first time users only" - doing it twice will not give you SGs

actually you can do it multiple times but on a diffrent device