My medical request came through GCkey, not through my regular email.
@shoaibmozid try contacting them through the webform first, and you can also ask for an extension, as you have not received the request letter. Include a screenshot of your ECAS showing that it says they have sent you the medical request, along with a screenshot of your GCKey account (specifically the "Messages about your Application" section on your application page itself) showing that you have not received the request, because once you have linked your application to your GCKey any request messages should be going through that and not the mail. I find I get a better response from submitting a webform vs calling the helpline.