We are arriving on First Class from Singapore Airlines at 6:20 am. We have separately booked (not on the same booking) the Lufthansa 8:50 am flight to Prage in business class. We have not been to Frankfurt Airport before. We need to make sure we can collect our luggage from the Singapore flight and check in with our luggage. Is the 2.5 hours enough time to do this. Can you assist with this ?