Gap Between sessions due to rescheduling by mentor

If the subscription is on 6months + 6 months basis, how is the calculation happening, is it no of sessions or no of days ? and what happens if mentor reschedules again and again and the gap between two sessions is greater than 14 days ? does that mean I lost a session in a week ? for example on session on Feb 23 and another on march 8 that's a 14 day gap the next session should ideally be at 1st march but mentor may not always be available then.