Visual Voice Mail with MEO

I have an iPhone 13 Pro and want to activate Visual Voice Mail. I received an email from Meo Support stating, "let me inform you that the Meo services are compatible with the Visual Voice Mail. However, the configuration is made on your equipment.". However, there is no option to configure the visual voice mail (under the voicemail tab in the Phone app). I do not get the "Set Up Now" option. It just shows the Call Voicemail button instead. Any ideas on how to set this up? I am getting little help from Meo.