Unable to uninstall or upgrade plugin in Moodle 3.2.3

[Coincoinlapin]

Hey there, I'm unable to uninstall / update the plugin from my website (using latest Moodle stable version).
There's no real error message that I know of when I click the update button:

Debugging output enabled
Downloading auth_googleoauth2 ...
<- https://moodle.org/plugins/download.php/13547/auth_googleoauth2_moodle32_2016061204.zip
-> /var/moodledata/temp/core_plugin/code_manager/distfiles/57471f9b44401acb2220e62ff5ae4930.zip

... OK
Validating auth_googleoauth2 ... OK
[OK] Name of the plugin to be installed [googleoauth2]

[OK] Plugin version [2016061202]
[OK] Required Moodle version [2014051200]
[OK] Full component name [auth_googleoauth2]
[OK] Declared maturity level [MATURITY_STABLE]

[OK] Plugin release [2.3 (Build: 2016061202)]
[Debug] Found language file [auth_googleoauth2]
[OK] Write access check [/var/www/auth]
[Warning] Target location already exists and will be removed [/var/www/auth/googleoauth2]

[OK] Write access check [/var/www/auth/googleoauth2]

Validation successful, installation can continue

Clicking the "continue" button just takes me back to the plugin overview page, with no update / no error message.
I can't even uninstall the plugin: there is no uninstall button, although I have deleted the user accounts of my students who had registered through the plugin.
Any help? I have access to the server & can provide more info if it helps.
Thanks.

[mbarrio]

I am having exactly the same problem trying to upgrade the plugin, but my Moodle is version 3.1.5.

[banha-serhii]

@Coincoinlapin you find some way for delete this plugin?