WPM not accepting typenames

Question

So basically i was writing a simple programm that would spot ennemies on the radar, however, when trying to use this line :

Features::WPM<int>(dwCurrentEntity + m_bSpotted, 1);

i get an error "unresolved external symbol "void _cdecl Features::WPM(unsigned long, int)" (?? $WPM@H@Features@@YAXKH@Z)"

could anyone give me hints or help me please.

This is what i defined WPM as :

//Features.cpp
template<typename T> void Features::WPM(SIZE_T address, T buffer)
{
    WriteProcessMemory(hProcess, (void*)address, &buffer, sizeof(T), nullptr);
}

//Features.h
    template<typename T> void WPM(SIZE_T address, T buffer);