The candida spit test is not at all reliable. You might still have candida, but the spit test won't prove it one way or the other.
You could have a mild yeast imbalance. If eating yogurt has been helping, then that might indicate that you do have an imbalance in your good bacteria in your stomach. This is not necessarily the same as full blown candida (serious systemic yeast). If you merely have an imbalance, that can usually be corrected fairly easily with daily high quality probiotics or sometimes even just yogurt.
If you truly have serious candida (systemic yeast), it is very hard to get rid of.