There are several troubleshooting things you can do before contacting a qualified vendor.
Contact your billing company to see if they are getting data for all units. Often, it’s simply a matter of replacing some batteries or tightening a loose connection. Your billing company can pinpoint meters that are not performing. If a battery replacement doesn’t work, or a block of meters are not transmitting data, make sure the transmitters and receivers are powered up.
If you need service, check your warranty paperwork. If your meters are no longer under warranty, contact a firm with submetering experts. Many issues can be avoided by choosing an experienced submetering company.
Quality submetering equipment has a long-life when properly installed and maintained.