poor service, no assistance received on fully paid trip

I booked a trip earlier n the year nd because of Covid I have had to cancel/postpone. I have not received assistance from Travelstart at all and I contacted them in June about the change to the travel plans. My original sales person was unfortunately retrenched as part of the impacts of the pandemic but it has been impossible to get anyone else to assist in this regard. The trip has been fully paid for along with insurance and all I want to do is confirm new dates or get the trip cancelled and refunded.