No voicemail and no call forwarding

I managed to contact webchat agent who reactivated my voicemail and they explained there is another option for attempting to forward calls on an android device. 

This is what I learned: In most cases, voicemail needs to be deactivated for call forwarding to work properly. Here’s why:

Since hen voicemail is active, unanswered calls are typically routed to voicemail instead of being forwarded.

but if your voicemail is deactivated and call fowarding isn't working than the phone just rings and hangs up.

If you want all unanswered calls to go to another number, you’ll need to turn off voicemail or adjust the settings so call forwarding takes priority.

To make call forwarding take priority after reactivating voicemail (you need smarty agent to do it and you have to wait for a bit)

Making Call Forwarding a Priority:
On most android phones, you can adjust this in your Call Settings:

Go to Settings > Calls or Supplmentary Services > Call Forwarding. (If you have a quite recent Galaxy phone you can just search for call forwarding in Settings)
Choose the type of forwarding (e.g., “Always Forward” or “Forward When Unanswered”).
Enter the number you want calls forwarded to.
Save the changes.

but voicemail will pick up...  can I suspend voicemail, service without deactivating it?

Dial the following code on your phone:
*61<forwarding number>**<delay in seconds>#

or to forward calls to 1234567890 after 20 seconds (about 4 rings), dial: *611234567890**20#