Upgrading Owncloud from 7.0.26

Hi, I am trying to upgrade owncloud from 7.0.26, when I was upgrading from backend then later it said that you don’t have php7 version on your server.

Later I have upgraded the php version to 7 and now when I hit to my URL then it says:
This version of ownCloud is not compatible with PHP 7.
You are currently running 7.0.26. Please use at least ownCloud 8.2.0.

I have tried manually upgrade with uploading folder at server end and changes in confiq file.

But then I get another error that Upgrade was Unsuccessful.

Please suggest to correct step for upgrading it. I have tried many ways and searched on web but no luck so far.

Please check the shared error above and let me know the solution.

Thanks

I would suggest a manual upgrade as described in the docs:

https://doc.owncloud.com/server/10.0/admin_manual/maintenance/manual_upgrade.html