Network problem where it keeps disconnecting

Recently my network keeps on dropping whenever I use the app I am working on. While I use emulator, this problem doesn’t occurred. The moment I test it on the actual phone, It looks like the app is forcing the disconnection.

I am on iphone 6 plus and IOS 9.3.2.

Does anyone else have this kind of problem? What have you done and how did it happened?

Thank you in advance