Redness and hardness in a surgical site suggest infection. Please check with your doctor if the wound is infected. In some cases the doctor will make a small incision and let the pus out. This takes only a minute.
Laparoscopic surgery has another complication, which rarely occurs with open surgery. This is infection with atypical mycobacteria. Your doctor should consider this as well. If the wound is infected with atypical mycobacteria, it will not heal by ordinary measures. Since it is now four months after the operation, this complication is a genuine possibility.