Cash payments

Cash still walks in the door. A regular drops by to leave a deposit for Friday. A large group hands over an envelope at the table. A walk-in pays upfront because they're not coming back. If cash lives only in the drawer and a notebook, deposits get forgotten, disputed, and written off when the staff member who took them isn't working.
Cash payments let you log a deposit against any reservation, by any staff member, at the moment it's taken. The amount attaches to the booking, the reservation flips to paid, and the entry shows up in the same end-of-day view as card and bank deposits.
Use it for pre-visit drop-offs ('I'll leave 100 euros for my birthday dinner next week'), in-person deposits for big groups, or full prepayment at the door for walk-ins. Every cash entry has a who, when, and against-which-booking — so the envelope in the safe always matches a record in the app.
The guest who paid doesn't need a reminder. The staff who took it doesn't need to remember. The manager at close doesn't need to reconstruct the day.