Upgrade v19.0.13.1 to 20 FAILED -> Update in process. - Could not open input file: occ - 'maintenance' => false, = STUCK

Debian 9
Upgrade v19.0.13.1 to 20 FAILED
It’s been 3 days at “Update in process.”
So I tried to run the CLI for the upgrade, but now any occ command gives: Could not open input file: occ
So then I tried to disable maintenance mode in the config file: ‘maintenance’ => false = Made no difference.
I removed the upgrade folder and the update folder in the data folder = Made no difference.
chown -R www-data:www-data /nextcloud/ = Made no difference.
I do not see any trace of occ in the nextcloud folder, like it’s disappeared.

I’m stuck, any ideas on how to proceed?

Thank you

I copy/pasted the missing folders from a backup, now I get:

/nextcloud# sudo -u www-data php occ
An unhandled exception has been thrown:
OCP\AppFramework\QueryException: Could not resolve OCA\Settings\AppInfo\Application! Class OCA\Settings\AppInfo\Application does not exist in /nextcloud/lib/private/AppFramework/Utility/SimpleContainer.php:107
Stack trace:
#0 /nextcloud/lib/private/AppFramework/Utility/SimpleContainer.php(116): OC\AppFramework\Utility\SimpleContainer->resolve()
#1 /nextcloud/lib/private/ServerContainer.php(149): OC\AppFramework\Utility\SimpleContainer->query()
#2 /nextcloud/lib/base.php(737): OC\ServerContainer->query()
#3 /nextcloud/lib/base.php(1093): OC::init()
#4 /nextcloud/console.php(49): require_once('/nextcloud/lib/...')
#5 /nextcloud/occ(11): require_once('/nextcloud/cons...')
#6 {main}root@mail2:/nextcloud# sudo -u www-data php occ maintenance:repair
An unhandled exception has been thrown:
OCP\AppFramework\QueryException: Could not resolve OCA\Settings\AppInfo\Application! Class OCA\Settings\AppInfo\Application does not exist in /nextcloud/lib/private/AppFramework/Utility/SimpleContainer.php:107
Stack trace:
#0 /nextcloud/lib/private/AppFramework/Utility/SimpleContainer.php(116): OC\AppFramework\Utility\SimpleContainer->resolve()
#1 /nextcloud/lib/private/ServerContainer.php(149): OC\AppFramework\Utility\SimpleContainer->query()
#2 /nextcloud/lib/base.php(737): OC\ServerContainer->query()
#3 /nextcloud/lib/base.php(1093): OC::init()
#4 /nextcloud/console.php(49): require_once('/nextcloud/lib/...')
#5 /nextcloud/occ(11): require_once('/nextcloud/cons...')
#6 {main}

At this point I’m thinking to try a clean install of nextcloud 20 and copy the data folder to the new location…???

I upgraded manually to 20, I was able to resolve any issues. All good now!