Firstly, very sorry for the late reply. Market Helper software is not compatible with all versions of Android OS because some versions like Jelly Bean and KitKat have security restrictions that prevent third-party apps from directly accessing them.
This app needs at least a 3.1 version or above or 6 android jelly bean phones to work or install properly without any problems.
So I'm not sure what's wrong with your phone but if you're trying to install an APK file on it then please try the manual installation method instead of using the Market Helper tool.
If something goes wrong still, let me know by commenting below so we can surely find a solution together.