Called and got an appointment to have the tank pum...

Called and got an appointment to have the tank pumped. Scheduled it for a time I would be home. They gave me the 8-12. They call me at 10:30 to tell me they can't service me today because of other emergencies. But they cantget to me until maybe Tuesday no guarantee. I'm trying to stop from having an emergency but of course they just want to wait so they make more money. I understand there is emergency tech but you should have someone dedicated to pumping to STOP and prevent emergency situations.b