Bacterial Vaginosis?

Has anyone had BV & can explain their discharge or symptoms? I’ve had reoccurring thin discharge that’s grey/yellow in color and smells weird. I’ve gone to the gyno about 3 times for this discharge and I have yet to get an explanation to what it is, so I’m getting frustrated b/c every time I have it, it goes away on its own after a few weeks, but it keeps coming back.