Could not process the operation. The instance of SQL Server is running under WOW64 (Windows 32-bit on Windows 64-bit), which ...

Could not process the operation. The  instance of SQL Server is running under WOW64 (Windows 32-bit on Windows 64-bit), which does not support Always On Availability Groups.  Reinstall SQL Server in the native 64-bit edition, and re-enable Always On Availability Groups. Then, restart the SQL Server service, and retry the operation. For information about how to enable and disable Always On Availability Groups, see SQL Server Books Online.