2003 sedan 5at . A/t check

When it rains I get transmission issues P0720 . I’ve replaced the vehicle speed sensor, valve body , relay by the tcm . I’ve cleaned every transmission connection and connection at tcm checked everything for corrosion nothing has been wet since this last heavy rain . I’ve pulled the fuse box cleaned it checked for corrosion . The last time I had this code I replaced the speed sensor and relay and it was fine until it rained heavy for 7-8 hours no wetness in cabin . Please I’ve done everything i can think of someone help me .