Delayed Voicemail on iPhone 12 Pro Max

For a couple of months my voicemails have been delayed by a few hours in showing up on my iPhone but within the last few weeks they are being delayed by 5-7 days. There are no carrier updates available and I cannot get my voicemail to refresh on my phone. I know I have about 8 voicemails I haven’t yet received, the oldest of which is from 7 days ago. Has anyone else had and been able to resolve this issue?