DLR Faceplate Error (???)

A Enduser reported a error on the DLR Faceplate in the HMI. The faceplate freezes and network devices cannot be seen (shows a "?" on each device). Did recommend a power cycle for the HMI and it was okay within a month and the error came back. I was thinking if the cause is due to the two HMI connections to the PLC. Is there something I'm missing out on the configuration or other things?

I've attached a picture of the error on the DLR faceplate.

PLC functions and HMI displays aside from the DLR faceplate are working properly.