Fair 15 day Ban?

Hello, I was just suspended for 15 days because I didn't want to continue playing with my team after a jungling Ekko didn't listen to me when I pinged retreat and he died trying to kill a Darius. Which for me, as a Nasus was my counter. Even though he died, I continued to play until Darius hit 6 before me and killed me under my tower when I was level 5. This was not the first time I was beaten by a half decent Darius. After he killed me, he snowballed by killing my team mates all around the map. My team flamed me for not being in my lane, but in my mind, I already knew I lost lane and would just continue to get killed by Darius had I stayed. So, I just went around the jungle farming until the inevitable lost. I don't see why I am the one who has to get suspended for 15 days when it was Ekko who didn't listen to me when I pinged retreat from his attempt at ganking. Especially, when I also said I had no mana to cast wither on him to secure a kill. Please help me out with getting my suspension revoked. Had I stayed, I'm pretty sure I would just get flamed for INTing, which I wasn't.