Redirection after enrolment not working

Since I was having the problem mentioned here I ended up creating my website at lavoixducorps.eu and install another wordpress instance in a subdirectory https://lavoixducorps.eu/academy/ running with another theme (Divi) working with lifterLMS without conflict. In admin-dashboard>course>access plan> I have set checkout redirect to dashboard.
I have installed lifterlms-customizations.zip and edited with
/**
* Redirect to a custom page on your site during LifterLMS Registrations
* @param string $url default URL
* @return string
*/
function my_lifterlms_reg_redirect( $url ) {
return untrailingslashit( get_site_url() ) . ‘/academy’;
}
add_filter( ‘lifterlms_registration_redirect’, ‘my_lifterlms_reg_redirect’ );

/**
* Redirect a user after sucessfully purchasing a course or membership
* @param string $url default redirect URL
* @param obj $order Instance of the LLMS_Order for the completed transaction
* @return string
*/
function my_lifterlms_completed_transaction_redirect( $url, $order ) {
return ‘https://lavoixducorps.eu/academy’;
}
add_filter( ‘lifterlms_completed_transaction_redirect’, ‘my_lifterlms_completed_transaction_redirect’, 10, 2 );

However when I test enrolment, I got redirected to https://lavoixducorps.eu/academy/?orders=orderNumber which display:
No Results Found
The page you requested could not be found. Try refining your search, or use the navigation above to locate the post.

The student is enrolled
The email for payment is sent to student.
The payement method is set to offline payement.
In admin-dashboard> reading> home page display is set to a static page> dashboard

How can I get the students to get redirect to the dachboard page after enrolment?

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