I would just play water ejection noises on you tube and just let the phone dry, basically it will sound like c r a p for a few hours then it will get better but if you play that water ejection sound on youtube it will speed up the process my S20 has swam in the bath loads of times and it always does that to me, if the speaker sounds muffled it's not damaged it just has a layer of water on it that needs ejecting