Urgent help I can't complete my online application

I am trying to create an application through the following URL
https://visas-immigration.service.gov.uk/apply-uk-visa then I pay for IHS then when trying to pay for the application I got the following validation message "choose a service" while there is no service to choose at the page.

Now I can't complete my application. An advice came from the visa center support to try creating a new application using "https://www.visa4uk.fco.gov.uk" now the new application request from me a new IHS payment. I can't link the IHS number that I already paid for to my current newly created application

Any help in this and what to do?

Do it from visa4uk and you can request refund for previous IHS. Or probably you will get it automatically.

Do you know more details about refund IHS? And how much time it will take to refund me the whole amount?