Update happens successfully but no changes are made

I have a spring boot program and right now my PutMapping function seems not be working as expected. Right now if I update the field in postman it says no errors but when I checked to see if the update occurred then there are no changes.

Controller:

    @PutMapping(path = "{bookingId}")
    public void updateBooking (
            @PathVariable("bookingId") Long bookingId,
            @RequestParam(required = false) Integer tickets ) {
        bookingService.updateBooking(bookingId, tickets);

    }

Service:

    public void updateBooking(Long bookingId, Integer tickets) {
        // checks if event id exists
        Booking booking = bookingRepository.findById(bookingId).orElseThrow(() -> new IllegalStateException(
                "Booking with id " + bookingId + " does not exists. "));

        if (tickets != null  && !Objects.equals(booking.getTickets(), tickets)) {
            booking.setTickets(tickets);
            booking.setAmount(booking.getAmount());
        }
        else {
            throw new IllegalStateException(
                    "The update was unsuccessful" );
        }
    }

Model:

    public Integer getTickets() {
        return tickets;
    }

    public void setTickets(Integer tickets) {
        this.tickets = tickets;
    }

>Solution :

You are not saving the updated object in the database.

    public void updateBooking(Long bookingId, Integer tickets) {
    // checks if event id exists
    Booking booking = bookingRepository.findById(bookingId).orElseThrow(() -> new IllegalStateException(
            "Booking with id " + bookingId + " does not exists. "));

    if (tickets != null  && !Objects.equals(booking.getTickets(), tickets)) {
        booking.setTickets(tickets);
        booking.setAmount(booking.getAmount());
        // save the updated booking in the database
        bookingRepository.save(booking)
    }
    else {
        throw new IllegalStateException(
                "The update was unsuccessful" );
    }
}