Copying a Magento 2 Site to New Domain ‘Remembers’ Old Site

I have copied a Magento 2 site from a test domain (testing.mytest.co.uk) to a live domain (mylive.co.uk). It has come time to upgrade the Magento version (2.2.5 to 2.2.6) and I receive the following error during readiness check:

    Found non-writable path(s): /var/www/vhosts/mytest.co.uk/testing.mytest.co.uk/var/.htaccess 

The reason it’s not writable is because that is not the domain that relates to where the site is now. It’s as if it is ‘remembering’ where it used to be? And I am unsure where this needs changing.

env.php and core_config_data have been updated.

Can anyone please advise?