Might ask the question - have you tried restarting the phone first?

Have you tried rebooting in safe mode to see if it works?

If you have a memory card, have you tried shutdown, remove the card and start again?

If safe mode works then perhaps try a factory reset and setup again?

If none of that works you could Google to find how to do a reset - I found some info here.

P9 is still great hardware, software is ok. I understand newer Huawei devices have a lighter weight EMUI.

Thanks very much for the responses. I had tried re staring the phone. If I Factory reset do I loose all my pictures and contacts?

There's a concept of hard and soft reset, with soft not losing data I think. You could see if you can find a method for that.

Before you do anything you must make sure all the content on your phone is backed up. You can copy it to your computer with a cable, sync it with dropbox, run backup software (Huawei probably includes some). I use Reslio Sync to sync to my computer. I use SMSBackupRestore to back up sms, though I don't much care if I lose it. And you should TEST and VERIFY that everything is backed up before you do a restore.

Things I back up

• Photos I take on the phone (I back this up to dropbox constantly and using Reslio Sync to my PC occasionally)
• My Nova launched layout
• My email client settings
• SMS
• Whatsapp does its own backup

Thanks again. I will double check my back up processes as contact and photos are work related and too important to lose, before trying the hard restart or factory reset.

You should have your phone linked to at least a Google account (or use something like a Microsoft account or Office 365)... In both cases Contacts would be automatically synchronised back to the service so you wouldn't lose that. 

As for Photos, if you use Google Photos or OneDrive then you should have the option to sync photos to these services automatically.

As for music, videos, make sure you have copies of those somewhere else.

I don't even think about contacts being backed up as they sync constantly with Google. I do use the Google Takeout feature monthly to back up my gmail, contacts, and calendar to my PC in case Google loses data or I lose access to it, with a monthly reminder to run an export,.

Phones should be treated as temporary, as they can be lost or broken any time. I suspect many people lose a lot of photos and such that are important to them as they don't have them backed up.

hisuite will do all that for you. then just reset phone and reload any data