I too have the same issue. Voicemails coming in delayed, typically the next day with visual voicemail. I have an iPhone 6+ and a second line with a Samsung Galaxy Grand Prime happens on both lines, both phones. How is this then a user side problem? Based on all the other comments on here, different phones, different accounts, different lines, it's obviously not related to the user. Thech Support should already be aware of and working on this, their internal problem. It been happening to me for over 8 months. Hasn't been critical until recently. Get tired of Tech Support trying to blame the problem on me. They should be monitoring this feed and just actually find out what the problem is and fix it already. Unless of course they don't want to because it's a new way to throttle bandwidth, or some other issue to make them more $$, or save $$ by not doing what it takes to fix it. Come on guys fix this, it's a super well known issue!
I am so sorry you are having issues with delayed voicemails! It is more than likely a network issue if it is happening on different lines. This is something that we can definitely look into with you via a network trouble ticket. If you have not already done so, please call us so our team of experts folks over the phone can gather some information from you and get the ticket opened.
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