Update creating new files

Hello,
I have Nextcloud up and running and I’m trying to update using the Admin UI.

The current version is 10.0.1 and Nextcloud 10.0.6 is available.
After trying to click the update, the system runs a Check for Expected Files.
However, i receive the erorr:

Check for expected files
The following extra files have been found:
updater-oc6cmiax71rl
updater.log

I can go into the nextcloud folder location and delete these files manually but every time I run the update button, these files are created again so there is no way to progress.

Does anyone have any idea how to get past this part?

Nextcloud version 10.0.1
Operating system and version Debian Jessie
Apache or nginx version nginx 1.10.3
PHP version 7
Is this the first time you’ve seen this error?: yes

Can you reliably replicate it? yes

The output of your Nextcloud log in Admin > Logging:

The output of your config.php file in /path/to/nextcloud (make sure you remove any identifiable information!):

<?php
$CONFIG = array (
  'instanceid' => 'oc6cmiax71rl',
  'passwordsalt' => 'xxx',
  'secret' => '2/xxx',
  'trusted_domains' =>
  array (
    0 => 'xxx',
    1 => 'xxx',
    2 => 'xxx',
  ),
  'datadirectory' => '/var/www/nextcloud',
  'overwrite.cli.url' => 'xxx',
  'dbtype' => 'mysql',
  'version' => '9.1.1.5',
  'dbname' => 'nextcloud',
  'dbhost' => 'localhost',
  'dbport' => '',
  'dbtableprefix' => 'oc_',
  'dbuser' => 'xxx',
  'dbpassword' => 'xxx',
  'logtimezone' => 'UTC',
  'installed' => true,
  'default_language' => 'en',
  'updater.secret' => '$2y$10$RjYaijrYZHJQQ.mqX.9uBuTnfumW49FAkua/mwEVymyq8dbpZ$
);

Thanks for your help!

@LukasReschke is the updater supposed to create integrity errors?