Insufficient Permissions to view this page

Hi

I am having a load of problems with my multisite and what it is doing with my main site. The WMPU dashboard had to be deactivated and then activated to get it to show on my network dashboard.

When I try to go to add new plugins via the WPMU in WordPress dashboard I am not allowed in because of insufficient permission.

I also have no way of loading or deleting plugins on my main network page.

Additionally, now my header is missing from my pages on woocommerce.

Am I missing something obvious? Everything is up to date and I am on WordPress 4.5.3

Can you help me out?

Thanks
John