Can people review me more than once on ProvenExpert?

Basically, yes but each person may only review you with the same email address once per survey.

Multiple reviews by the same person are only permitted if you ask them about different services/topics, i.e. with a separate survey each. See also: How do I create a survey?

Tip:

You can ask the reviewer to revise their review, e.g. if a negative review has been resolved. See also: Asking the person to revise a review.