If I really enjoy playing a champion but I don't do very well with it

Hi there people, so, this is my problem, I started playing LeBlanc and I managed to reached Mastery 5 with her, the highest grade I could reach with her I believe it was A+ or something in a really good game. The thing is I suck at the beggining of lane phase, I have poor cs with her even tho I usually never get killed by my lane opponent 1v1, usually I die for ganks. My decision making could be better but sometimes I make really poor decisions. The last game I played with her I previously watched a lot of videos on her and praticed in the practice tool, then I went to play and my lane was being camped by the other team's jungler and I had 0 ganks from mine even tho I asked for it and with all that I gived up on playing her. I'm usually unlucky with the teams I have because or either they fed or become afk, I know I could carry a Game on my own and if I am not feeding myself it's my own fault, but how am I suposed to Carry a team if I can't play her very well even tho I really enjoy playing her? Should I keep practicing with her? I just recently reached level 30 btw never played ranked games until the date I am publishing this.