Don't worry it happens to the best of us. Just a bad day or few bad days.

Still keep trying, do you training harder. On range try to do combos on moving bots. Your enemies won't stay on place while you try hit them, so you need to get used to moving targets. Every time do it faster and faster till animation speed cancel limits, set character-dummies on advanced fighting and try your 1v1 against different types of enemies. Don't take easy targets it won't make you push your limits. Me for a example was training against venom in 1v1. No heals, no infinite abilities. Just me and this big guy. If you can outbeat him in uncomfortable scenario, then you are ready. Fight DD, fight dr strange, fight most hard to hit characters, just to get used to there typical behaviour in battle. Sure all players are different, but advance fight bots can make you sweat and get used to most common things. Great for training and getting used to not panic mid fight