Auth PHP Fatal

We’ve started getting a PHP fatal error when saving Authentication settings in FluentCommunity Pro?

Error:

PHP Fatal error: Uncaught TypeError: array_intersect_key():
Argument #1 ($array) must be of type array, string given

Stack:

FluentCommunity\Framework\Support\Arr::only()
FluentCommunity\App\Services\AuthenticationService::formatAuthSettings()
FluentCommunityPro\App\Http\Controllers\ProAdminController->saveAuthSettings()

File:

/wp-content/plugins/fluent-community/vendor/wpfluent/framework/src/WPFluent/Support/Arr.php:626