How to change the ticket Quantity?

If the  ticket is not sold , the Ticket quantity field is editable and  you can   make the changes in that.   However, if  even one ticket  is sold, the ticket Quantity field becomes non-editable, in that case, a  new  Appears at the bottom of the Edit Ticket popup named Update Ticket quantity.  Please use this option to  make changes to the ticket quantity field.  

   

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