I constantly have this problem after I migrate websites. Sometimes simply deactivating the license and activating works but many times it doesn’t. I have been in contact with support and they offer a few suggestions which sometimes work but again often don’t(see below from support).
There is obviously a problem with how the license key is registered it would be great if ACF could address this.
From ACF Support
When ACF loads the license key information saved into the wp_options table, it validates the data saved against the current URL. If the website’s URL is different to the URL that was saved, ACF will not load or display that license key.
Therefore, migrating a site invalidates the current activation since the website’s URL will be different to the URL that was saved.
When this “issue” occurs, all that is needed is to enter a valid license key into the “Custom Fields > Updates” page. This will ping our server and register that URL with our API and thus allow package downloads for your website.
When experiencing “Update package not available” issues, 99% of the time the problem is due to something wrong in the download URL. Which is fixable by deactivating and then re-activating the ACF PRO ‘license’ activation from the “Custom Fields > Updates” page.
Are you able to see this activation in the list of activations on your online dashboard?
Would you please confirm if the plugin is correctly activated and the website URL visible from your online account dashboard by logging in to your ACF Dashboard, then navigate to the Licenses tab and click on the “Manage Activations” button?
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