I would also like an answer to this question. Applying from Australia.

Hello, I wish to cancel my son's UK visa. I have emailed CIH@homeoffice.gov.uk with subject line "POST BIOMETRIC REFUND REQUEST" with our details 8 June 2021 and got an Auto response but have heard nothing further as of 8 July 2021. I emailed again today. Does anyone else have feedback about this em...