I went onto setting and scrolled down to the 'command' section and it was on hdd1,and I mistakenly pressed it on to hdd2,a caption came up to press a button within so many seconds which I did not do,so it went onto hdd command 2 and the remote would not then work.
Any ideas please.

Alan hare, April 2017

Yes. Read the manual.

Especially page 44, towards the bottom of the first column and page 13, item 7.

https://www.sony.co.uk/electronics/support/res/manuals/2689/26896341M.pdf

acp, April 2017