Updating to iOS 14.1 or 14.2 to iPad Pro 12.9"

Dear all,

I'm struggling to update my recently purchased iPad Pro 12.9' (June 202) to iOS 14.1 or 14.2, it wouldn't update to 14.1 due to a failed download error, I thought I'd wait for iOS 14.2 with the hope that this would solve it, however when released I had the same error. I then restored the iPad back to factory settings thinking this would solve the issue however again I have the same error message. I've spoken to Apple support this morning and they've advised updating the iPad via my MAC which has produced the error message "There was a problem downloading the software for the iPad "Ashley's iPad". An unknown error occurred (-18)". I was also advised to potentially use a different broadband network but this is also having the same error message.

Any advice would be greatly appreciated. Thank you in advance.