A printer that executes printing based on a print job includes a memory containing instructions, and at least one processor for executing the instructions to operate as a first receiving unit configured to receive from a computer a print job instructing the printer to print a plurality of copies using a plurality of feeding trays, with a different feeding tray instructed to be used for each of the copies, a display unit configured to display the number of copies of the print job, and a second receiving unit configured to receive an instruction from a user to change the displayed number of copies of the print job. In addition, instructions are executed to operate as a cancelling unit configured to cancel, based on the changed number of copies, the print job, the number of copies of which has been instructed to be changed.