Is this treating a customer fairly..

I want to share my Mango Airline experience with you and you can decide if this is treating a customer fairly. We are busy relocating from Gauteng back to the Western Cape. My husband is already in Cape Town. On 06th July I made a booking with Mango as my daughter and I need to travel down to assist with the relocating and buying of property. Tickets were booked for the 8th and the 11th of August and I paid R3 437.92. On Saturday the 1 st August I got an e mail confirming the first flight JE 129 was cancelled. I phoned the call centre and was told to phone during the week as the new flight schedules were not available yet. Sunday afternoon I got another e mail confirming the other flight JE 156 back to Gauteng was also cancelled. I phoned early on the 3rd and got confirmation both flights have been rescheduled but nothing happens automatically and I need to make n a new booking. I requested a refund to look at alternative options but was told that Mango doesn’t do refunds. They only issue vouchers which must be used for future Mango flights. The call centre consultant then made another booking for the exact same date and exact same time as the cancelled flights, only a new flight number. Flights JE127 and JE 182. He then told me I had to pay in another R2 485.08. I do understand that flights can be changed according to circumstances but I feel they must at least offer the option of a full refund as they did the cancelation of the flight. As an alternative rebook but at the same rate. The worst is not the price increase of R2 485.08 but everything else stays the same. Same date and same time. As he said to me. The only option is to take it and pay in the difference or travel later when the price is lower and I don’t have to pay in so much.