On my s8+ works so bad after the last update and since a few days now it only works sometimes,and when is working is so daam slow.
Have you tried re-training Bixby ?
Sometimes a soft reboot by turning the device Off and On can help.
That or perhaps consider Google Assistant.
Daily Driver > Samsung Galaxy s²³ Ultra 512Gb in Phantom Black.The advice I offer is my own and does not represent Samsung’s position. I'm here to help. " This is the way. "