PSA: if you are an one trick, ask your team to secure your champ for you
If you only play one champion and you suck at all other champions, ask your team to first pick your champion for you. If your champion is banned, just dodge. There is no reason for you to play a champion you don't enjoy playing and lose your team the game because you are inexperienced with the champ. Just dodge. 3lp and 5 minute is better than feeding getting flamed for 20 minutes.
Btw it is not a good idea to be a one trick if you wanna climb.
PS: don't be a one trick of champions with high ban rates.