Finally I manage to pay for priority from different link and I got below email. Is this correct?
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Thank you for payment through the VFS website.
Please print the attached online transaction receipt and include a copy of it in your packet of documents
that you will submit to the UK Decision Making Centre in New York or Sheffield, depending on your visa category.
If you purchase Courier Service, please be sure to select “Print AWB” or “Email AWB” on our website. If you do not receive your courier Airway Bill, please be sure to check your Spam folder. If you have any issues downloading or receiving your Courier Airway Bill, please send us your receipt and an explanation of your issue to:
UKVI.Feedback.USA@vfshelpline.com. Please be sure to include your GWF Number in the subject line of the email and we will be happy to assist you!
Kind Regards,
VFS UK Visa Application Team- USA