Best answer by Max
Sorry to hear of the issue that you are experiencing and thank you Gordo26 for your assistance in this matter.
If you can still interact with the phone there is the option for a factory reset within the settings of the device - Settings> Backup & Reset > Factory Data Reset - please bare in mind that this will wipe the internal memory of the device so if possible backup any important data to a external source like a PC or a Mac.
Please let me know if this helps and how the device is behaving after the reset if it is possible. If the issue is still persisting the best option would be to send it to our technicians for a more hands-on approach within the service center.
For the UK region you can contact us directly via mail chat or hotline ( free of charge of course at 08000886700 ) at https://consumer.huawei.com/