It's possible that your neighbours may have a new connection or stronger signal than yourself which is affecting your pod.
Have you run any checks via the Virgin Media Connect App?
Once the App is open select the Broadband option from the bottom menu. This will display the My Devices page. Click on the My Network tab/icon. This screen will show you how many devices are connected to the Hub/each Pod. Tap on a Pod for more information and then tap Connection from this list.
If fair is showing, this indicates that the Pod(s) you already have may not be in the optimum place for performance. It is advised that you choose another location in the home, allow 2-3 minutes for the Pod to reconnect (wait for the light on the Pod to stop flashing) and then re-open the app and try again.
The app can be refreshed from the My Network or My Devices page by dragging downwards from the center of the screen. Tap Let's improve it to progress to the Refresh WiFi screen. (Note: Refreshing the WiFi can take up to 15 minutes.) Placement Tips can be used to help you decide where to try placing the Pod within your home.
Once all this has been done, it should advise whether another pod will help. If so, please screenshot this and post here and a member of VM Forum Staff should be able to order another pod for you.