The calendar is a picture of your bookings, so when it looks off the cause is usually one of a few rules about what it shows. You get to it from Calendar, which has Day, Week and Month views.
A booking is missing
The calendar shows only Pending and Confirmed bookings. Once a booking is marked Completed or Cancelled it disappears from the calendar. Find it on Bookings, where the buttons All, Pending, Confirmed, Completed and Cancelled filter the list.
A stay looks one day too long
A boarding stay appears on every day from check-in through check-out. So a dog staying two nights, 10th to 12th, shows on the 10th, 11th and 12th. Capacity counts nights only: that dog uses the 10th and 11th nights and none on the 12th.
A day only shows four dogs
Each day shows the first four bookings and then something like +3 more. Open the Day or Week view to see everyone.
A booking you do not recognise
Pending bookings appear too. A card booking that is still waiting for payment sits on the calendar until the hold time runs out. See A booking is stuck on Pending.
The colours are not what I want
Colours come from each service. The owner can change them from More → Business → Services & Pricing: open the service and set Calendar colour. The key above the calendar lists each service, with a Change colours link for the owner.
Dates or times seem to be a day off
Check your time zone in Settings → Business & payments. See Set your time zone, currency and sales tax.
Related: Calendar, week view and printable schedules, See who is coming in today.
Still stuck? Open More → Dogly Support and tell us which date looks wrong and which booking you expected to see. A screenshot helps.