Debugging a module issue can prove impossible without good repro code or a proper snippet. C++ modules can do basically anything to fuck things up, so if you really need good advice you should start giving us code.
My best guess would be that you are using
get_amxstring() (
which uses static buffers) for your forward parameters. This is dangerous because when plugin use natives from inside your callback, those natives
will re-use those buffers for themselves. If this is the case here you should be using
get_amxstring_r() to move the strings into your own buffers.