Try this….

https://www.koodomobile.com/en/help/voicemail

Customize the number of seconds your phone rings before your calls go to voicemail (i.e. 5, 10, 15, 20, 25, or 30 seconds) (Minimum 5 seconds = 1 ring, Maximum 30 seconds = 6 rings).

1. Dial *#61# and then press the call/send icon. This will display your __voicemail access number__ (this is not your phone number).
   

The following ten-digit voicemail access number shown in bold is an example: * 61 * 2265804001 * 11 *10#

If you don’t see the voicemail access number after entering this code, or if you get an error message, please schedule a callback through Koodo Assist and a rep will be happy to help you with this.

If you see the voicemail access number, write it down somewhere. When entering this code, do not add +1 in front of the voicemail access number, as the system adds this automatically.

In the example above, the number 10 represents the number of seconds before voicemail picks up. The table below shows the approximate number of rings to voicemail:

10 seconds = 3 - 4 rings to voicemail
20 seconds = 4 - 5 rings to voicemail
30 seconds = 5 - 6 rings to voicemail

2. From your phones’ dial pad, enter __* 61 * voicemail access number * 11 * number of preferred seconds #__ then press the call/send icon.
   

• You should see a message: “Setting Activation Succeeded, Voice Call Forwarding When Unanswered.”
• Press “Dismiss.”
• Dial *#61# to confirm everything is in order.

Unfortunately the maximum is 30 seconds or about 6 rings. The answering machine will likely need adjusting to 30 seconds then.

The info to change is here: https://www.koodomobile.com/en/help/voicemail

Customize the number of seconds your phone rings before your calls go to voicemail (i.e. 5, 10, 15, 20, 25, or 30 seconds) (Minimum 5 seconds = 1 ring, Maximum 30 seconds = 6 rings).    

  Dial *#61# and then press the call/send icon. This will display your __voicemail access number__ (this is not your phone number).  The following ten-digit voicemail access number shown in bold is an example: * 61 * 2265804001 * 11 *10# 

If you don’t see the voicemail access number after entering this code, or if you get an error message, please schedule a callback through Koodo Assist and a rep will be happy to help you with this.  If you see the voicemail access number, write it down somewhere. When entering this code, do not add +1 in front of the voicemail access number, as the system adds this automatically.

  In the example above, the number 10 represents the number of seconds before voicemail picks up.

The table below shows the approximate number of rings to voicemail:  10 seconds = 3 - 4 rings to voicemail 20 seconds = 4 - 5 rings to voicemail 30 seconds = 5 - 6 rings to voicemail     

From your phones’ dial pad, enter __* 61 * voicemail access number * 11 * number of preferred seconds #__ then press the call/send icon.      You should see a message: “Setting Activation Succeeded, Voice Call Forwarding When Unanswered.”     Press “Dismiss.”     Dial *#61# to confirm everything is in order.

In one of the Knowledge Base article by @Chris Koodo , in the compatibility section, it stated that the method does not work for Wireless Home Phone.  

Link to KB Article:

These are excerpts from the TELUS Home Phone page, replacing TELUS with Koodo in some areas.

From your home phone, wait for a dial tone, then dial *94. You should hear 2 quick beeps. From your phone’s dial pad, enter the number of rings (from 2 to 9 rings) you want the caller to hear before the call is transferred to voicemail. Example: for 7 rings, press 7 on your phone’s dial pad. Hang up. Your number of rings should be successfully adjusted.

If you also use an external answering machine, you may need to change its settings, too. Voicemail may go to either the Koodo voicemail or your external answering machine, whichever picks up the call first.

For example, if your Koodo voicemail is set for 5 rings but your answering machine is set for 3 rings, your voice messages will go to your answering machine. Keep us posted and let us know if this worked or not.

https://www.telus.com/en/support/article/adjust-home-phone-rings 

Just gave that a shot.  Method does not work in Ontario.

Going to https://www.telus.com/en/support/article/adjust-home-phone-rings  resulted in - “Sorry, the content you are trying to access is not available in your province.”  I’m in Ontario.

Denis’ and Goran’s comments, while informative, do not apply to Koodo’s Wireless Home Phone.   They look like the instructions to access your voicemail on your cell phone.

I have no idea why location makes a difference, maybe so Telus doesn’t compete with Koodo in the same province for virtually the same service.  

Regardless, seems ridiculous why Koodo would not allow the number of rings to change.  There is nothing on the VM menu when I go to it from the phone plugged into it.  Also disappointed that this service even existed and Koodo provided no information on it when I purchased the hub.

Found the user guide for my hub under “User guide” at The 101 on Koodo wireless home phone | Koodo Mobile and it does not say anything about adjusting time to answer.  Unbelievable!