I can see the exported function in the mymodule.js however the await _jsRuntime.InvokeAsync cant find it

I had a C++ project that I used to build using a makelist.txt file. The project has Array.hh MyLib++.hh MyLib++.cc . All three modules are defined within the same namespace. In blazor webassembly, in the server side c# dlls I want to call the function xpower which is found in MyLib.
I have tried with many options but no luck. The await _jsRuntime.InvokeAsync("_xpower",...) returns runtime error (visible in the console) with reason _xpower undefined. using Typeof Module._xpower returns undefined too.
thanks.