Thanks Jock1e :)
The e-mails do not actually transfer and download to the phone, they stay on the VM server and are viewable via the Android app. When accessing them on my laptop I use the VM website's own online e-mail page, not an e-mail client such as Outlook.
This does mean that ALL my old e-mails are still on their servers, which is great for me to access old ones when I want to, but it's the newest ones I can't seem to view on my phone.
Anyone else any ideas please?