Wrong currency conversion for monthly spending

[Berkay]

Hi,

My mother's visitor visa application was refused for the following reasons. The caseworker made an error when converting the monthly expenses (IRR 50000000), which resulted in the incorrect amount (£894). This is a major mistake that negatively impacted the application; I have no right to appeal and have no idea what to do.

What was written in the letter is shown below:

"The Home Office would normally use the OANDA exchange rate to convert Iranian Rial (IRR) to GB pounds (GBP), however this is not the effective exchange rate available to the general public and does not provide an accurate assessment of your funds. Instead I have converted your funds in IRR to GBP using the UK Foreign, Commonwealth and Development Office’s (FCDO) consular rate of exchange of 1 GBP = 770,600 IRR as on the date of this letter"

"On your VAF you state that you are retired, receive annual income of IRR 2223631332 (£2885), and spend IRR 50000000 (£894) per month. This indicates that your finances are subject to great demands, as your declared living costs significantly outweigh your income. Therefore, I am not satisfied that the documents provided demonstrate that you have economic ties to your home country which will encourage you to leave the United Kingdom should be granted a visa."