Hi everyone
I just wanted to thank you all for your suggestions/solutions to my problem, I finally have a fully working loco with all the appropriate sound and functions.
Firstly I deleted the loco from the Z21, I then placed it onto the programme track and reset it via the reset to factory settings CV8 having first adding it back on to the Z21, I used a different address and happy days it worked.
Thanks again for everyone’s advice and tips.
Regards Duncan