Help please, someone stole my codes

I am working in a BPO company, where I was asked a favor to help the business. The management want to come up with a certain tool that the agents will be able use and help them lower one of the metric called Average Handling Time (AHT). To make the long story short, they asked me to come up with that tool. At first they want me to create an auto notes for the agents using microsoft excel which is impossible because of computer restrictions of the company. Since i am an IT graduate i know an easy way to do it which is using HTML. I was able to finish the tool and they liked and love it. It was implemented and rolled out to all agents which they are all using now. First, i am not paid for doing this considering i have used a programming language, it took almost a month for me to finish it and had to make different versions as well. Then all of a sudden another department in the same conpany, copied the project i created, they edited it (though obviously its mine as my name still appears at the copyright foot note). They never asked permission from me which makes me feel bad, and felt like they steal my codes.


I am really hoping for a help. Please help me. What should i do for my rights?