MYSQL PHP 8 STORED PROCEDURE TO CHECK POSSIBLE WORKSHOP based on consultant availability or unavaible dates

On team viewer , no sending files i will show you the project on my pc and you'll fixe on my pc . looking for an experienced programmer with strong MySQL and PHP 8 experience to create a stored procedure that will check workshop possible dates to be booked based on availability of the teacher who is going to perform the workshop, unavailability date, depending on a consultant’s availability. The expected outcome of the stored procedure is to return a list of available dates for a specific workshop for the next two weeks. I already have the procedure but its not working properly the result are wrong :