I have a friend who recently had the experience of reaching baggage claim at Piarco and not finding their bags. Other passengers on the flight had the same issue. He made a report at the far end of the baggage claim hall to an agent at the counter who had a sign for the foreign airline company above them. He received a receipt of the claim and was told to go through the red line. The agent was unable to give any information about the location of the bag and was only there to record the complaint. A phone number was written on the top of the receipt and he was told to call it for more info. This process would be the same for any airline. Here he was told to walk through after the officer read his papers for the lost bags.
When he got home that night he downloaded the United Airlines app which allowed him to input his flight info and get to track his bags. The bags apparently did not get transferred to the new plane during a connection.
The next day he called the number that he was told to, however he was transferred to the mechanical maintenance department for Caribbean Airlines. The man who answered it said he had no idea why his number was given out and to call the main Caribbean Airlines number. When the main number was called and the operator was made aware of the situation, she apologised repeatedly for the issue but said that nobody there could help because it was a different airline. She also said that their number may have been written because they simply have a big presence in the airport.
Eventually, he was given the correct number to call which is for Airport Authority of Trinidad and Tobago 868-669-4868 ext 7512/7513/7514 baggage department.
It took a few attempts to speak to someone because the calls kept dropping and the woman was not able to hear him sometimes. Apparently they have major phone issues. The agent was able to confirm the information in the app which was that the bags were not brought to Piarco and they were expected to arrive the next day. She reconfirmed the contact info and said the bags would be delivered free of charge.
The next morning the bags were dropped off to him.
I recommend you take a picture of the contents of your bags as well as the outside so you can have more evidence if you have to make a claim for a lost bag.
Check the airlines app if they have one. This would be cheaper and probably quicker than calling an international number to speak to an agent.
How to track lost baggage in Trinidad and Tobago
Find lost luggage piarco airport
Port of Spain United, Caribbean, American, Liat, Jetblue, British Airways, Conviasa, Copa, Surinam airlines