If your booking page says:
Unfortunately, there are no available times that match your requirements.
then something is filtering every slot out. Work through these in order. The first three cause most cases.
Go to Availability and check the day in question actually has hours set. A day with no hours produces no slots, and it's easy to leave a day switched off when you first set the schedule up.
Check you're looking at the right schedule too. If you have more than one, make sure the event is using the one you've been editing.
Still on Availability, check the Date overrides section. An override marking a specific date as unavailable beats your weekly schedule for that date.
Overrides set months ago for a holiday are a common cause of a single mysteriously empty day.
Open the event and check Minimum booking notice. This blocks slots that are too soon.
If it's set to 24 hours, nothing in the next 24 hours can be booked, so a prospect looking at today and tomorrow morning sees nothing. Set to 2 days, the whole of tomorrow disappears.
This is the single most common reason a booking page looks empty while the calendar looks fine.
The same setting in reverse. If the maximum advance is 30 days, nothing beyond 30 days is offered. A prospect browsing forward to next quarter sees an empty calendar.
If you've connected Google or Outlook, anything marked busy on that calendar blocks the matching slots. Open the calendar itself and look at the day.
Some entries deliberately don't block, so don't be thrown if you see something on the calendar and the slot is still offered:
All-day Working Location entries
Events you've marked as Free rather than Busy
Birthdays
Invitations you've declined
Buffer before and buffer after reserve time around each meeting. With a 30 minute buffer either side, an existing meeting blocks an hour more of your day than its length suggests. Stack a few meetings and a day can fill entirely.
If Look Busy is switched on for the event, SalesCal deliberately shows only a limited number of evenly spaced slots per day, even when you're wide open.
That's the feature working as intended, but if you've forgotten it's on, a sparse calendar looks like a bug. Check the event settings and either turn it off or raise the slot count.
If the event caps bookings per day, days that have hit the cap show nothing further.
An event that isn't active won't take bookings. Check its status on the Events page.
On an event with several hosts, a slot appears if at least one host is free. If the calendar is empty, every host is blocked at every time, so check each host's availability and connected calendar, not just your own.
Also confirm each host still holds a sales seat. A host without booking access can't take bookings.
Check the page as a prospect would, in a private browsing window, and note the timezone shown in the picker. If it's not the timezone you expect, the slots may exist but be displayed at hours you're not looking at.
If you've been through all of the above and slots still don't appear, get in touch with the event link and the date you're expecting to see, and we'll trace it from our side.
