Your voicemail is also now migrated to Unified Messaging in Office 365 - Voicemail in the Cloud.
Here are some instructions in accessing your voicemail:
Press the "Messages" button on your phone.
Enter your PIN followed by the # sign (it should be the same PIN you've been using before the migration).
To access your voicemail from a different phone (e.g. from a cell phone, other office phone, home landline), dial the pilot point 675-3273
Enter your 5 digit extension, enter your PIN followed by the # sign.
For any voicemail problem, please contact the Helpdesk @ ext. 53921 (675-3921, email help@byuh.edu), a ticket will be dispatched to the ITI Telephone Services.