Reflection bc30002 type is not defined vb.net

I am trying to connect Reflection mainframe via vb.net code. Earlier it was working fine with Attachmate code but when I am replacing EXTRA with EXTRACOM then I am getting error bc30002 type not defined error for below statements

'working
Private sys As EXTRA.ExtraSystem
Private ses1 As EXTRA.ExtraSession 'the session object

'Not working
Private sys As EXTRACOM.ExtraSystem
Private ses1 As EXTRACOM.ExtraSession 'the session object

Although there is not compile time error but build is failing and error shoeing in output window.l