Updated (Please don't consider my last post as it is incomplete):
I again installed the plugin digress.it.Then the sites including main sites seems working.Then I deactivated it .Now I observed a word like: Broken theme .So I installed a new theme.My main site started working and seems as problem solved.By this it is clear that I would get 'Blank page error' If I delete the plugin as the plugin's default digress.it theme still remains there.So I should delete it and install a new theme.
The problem exists again If I use digress.it
So I deleted the plugin and deleted the entire twenty twenty theme and reinstalled it.
The following problems are still persisting .
1)All other sub-sites except the main site are appearing as blank pages.How ever the dashboards are Ok.I tried reinstalling the themes for every site and working well now.
2)Newly created sites are having the error as :
Fatal error: Call to undefined function wp_get_current_user() in /home/asshu/public_html/iliked.info/wp-includes/capabilities.php on line 1059 (I doubt the cause for this error is something else)
Could you help me to resolve this issue.
Thank you !