Thank you for the replies
I have emailed iwown support and shall see what they say.
In the meantime I followed Cuttlas's link (the download pages wouldn't translate so I'm not entirely sure what I clicked on half the time
) and Chrome didn't kept flashing up warnings about the site and malicious software, but did find some for the i6 pro in the end. The DFU in nrf toolbox worked and the band is working again, which is great news.
The downloaded firmware is an earlier one and only has running as an option in the training section. It originally had cycling and a few others as well so I'm going to keep looking for the later firmware.
(For anyone in a similar situation I now have 126.96.36.199 and 188.8.131.52 for the i6Pro.)
Thanks for your help.