I was playing soccer 3 weeks ago and was kicked just above ankle, bruising gone but still swollen/tender, how can I recover?

Physical therapy. That area contains many tendons that control ankle function. It is possible that they are weakened, after being kicked there. You may require physical therapy, to restore full function.
Time, medical care.. The first thing to do is to assess the severity of the injury. You may have anything from a soft tissue contusion to a bone contusion to a fracture. You should see a doctor and get an x-ray to rule out fracture. If it isn't fractured, the injury should resolve with time, but even 3 weeks may not be long enough. Continue using ice, gentle massage, ankle range of motion, and protected activity.