You are offering 'free delivery' - as you are listing with a postal service offered, you need to send on a USB stick.
Or, as stated below, you need to use the classified ad format.
You also need to register as a business seller.
Electronically delivered items need to be listed in the Everything Else > Information Products category in the classified ad format. If the classified format isn't available on the seller's eBay site, electronically delivered items are not allowed.
https://www.ebay.co.uk/help/policies/prohibited-restricted-items/electronically-delivered-items-poli...
"There are two ways to be fooled. One is to believe what isn't true; the other is to refuse to believe what is true.”
Søren Kierkegaard, Danish philosopher (1813 - 1855)
