Lost suitcase ref FLRKL 21528

I flew from Accra via Amsterdam to Florence on KLM on Sat 22 June for a 2 week holiday and checked one bag into the hold. When I arrived in Florence 23 June late morning my suitcase wasn’t there and I was told it would arrive in Florence the night of 23 June. I filled out the forms and waited at my accommodation in vain the next day for the bag. I proceeded with my holiday tour wasting a lot of time money and effort communicating with KLM via phone, e mail and WhatsApp to keep them abreast of my travel itinerary but to date they have been unable to deliver my suitcase to me! As I have a set itinerary I was able to provide KLM with full details of my whereabouts. I am now in Greece, the date is 3 July and I have still not gotten my bag or an undertaking of any sort from the airline! This has spoilt my holiday and I did not expect such poor service from what I thought was a reputable airline. They did confirm that the bag was on flight to Florence on 23 June KL1643 and was picked up by a carrier but no carrier has since contacted me. KLM lost bag reference is: FLRKL 21528 Baggage tag nr KL 318028