No refund and no help with rebooking

I cancelled my flight due to being on the red list in The UK in December. Budget air gave me an open air ticket from Virgin which can use before December 2023. I want to now rebook and use this open air ticket and rebook with them. I constantly have conflicting stories from different agents on the site. Some say I can get a voucher from Virgin Atlantic but I've tried to get a voucher but Virgin send me back to budget air as they cannot interfere with a third party's booking due to contracts. I tried to rebook with my open air ticket money on Budget air but now they quote me R36900. I have researched and on Budget air a flight is R13726 on Virgin and on Virgin's website the same flight is R21400. I will never be able to afford this ticket and the quote they are giving me. I would like a voucher from budget air to rebook a whole new flight.

It is not my fault firstly couldn't afford hotel quarantine at R52 000 per person and secondly had to spend 10 days there and come out and have 2 days to see my family. it was not logical at all.

The help budget air gives is disgusting and unhelpful and all they want to do is for us to forget about our ticket and keep our money.