Srilankan Airlines — luggage missing

Here by i file a complaint about that i missed my hand lagguage during my travel on last sunday dated 26/05/2019 en route to kuwait - colombo - trichy. Suddenly i informed to the airport officials about that and they replied that they will get lagguage within two days. After that they told me via mobile that i need to pay rs. 16, 250 for the excess luggage. But i don't want to pay that much amount. There is no worth in that lagguage for the sum of rs. 16, 250. But however i need my lagguage. So kindly help me regards this complaint. Thank you.