LAM Customer service

I had a ticket booked return to Maputo for the Easter weekend 2020. Because of COVID, I couldn't travel. My booking was through Flight center who mentioned I had a voucher to use before December 2020, when travel opens again. Flight Center has attempted to rebook for me now that travel has opened again, even copying me into to the emails to LAM. No response on many occasions. I strongly recommended anyone wanting to travel to Mozambique to look at alternatives, as LAM are extremely inefficient with no customer service skills and aptitude. Flight Center have been extremely helpful.