Hypnosis can work wonders - at least it seems. Even within one single session. But it would be highly unprofessional to make any promises about how many sessions your issue needs to be released.
It would be wonderful to predict the number of your sessions. But in reality some may be needed to get full results. Generally speaking, most issues can be cleared between 1–3 session. Sometimes it needs more time.
Think of your mind as having layers. Sometimes you have to work layer by layer to get to optimal results.