Disappointed with Mango airline customer service and lack of empathy

I booked flights for myself and my mother to travel on 03 January EL to JHb. On the 02 January my mom was admitted to hospital and later passed on 10 January. On the 03 January when I was travelling I informed Mango and they recorded that in their system for her to travel at a later date. When she passed on I informed them and asked for a refund. Dearth certificate was attached in the email. Email was acknowledged on 09 April for processing . 22 April I received confirmation that refund is being processed and will be paid soon. To date I have not received a cent from Mango for my moms ticket after numbers of attempts and conversations with one of their staff members who confirmed request is being processed. Few weeks back email bounced back with email to contact business review team for refunds etc. Business rescue team has not even acknowledged my email as I forwarded them all the email threads relating to my refund. I have given up on this refund.