I had always assumed that the cellular signal was just a backup for the wifi. Or at least, if one went down it would just use the other.
Cellular is primary, wifi is concurrent backup. Looks like at the time both of those were out, a reboot would typically be the first recommendation if you do not have any issues with wifi at the time.
It looks like you’ve resolved this condition however as there is no current trouble and both cellular and broadband pings are successful when sent today.
Another consideration would be updating the firmware to one of the latest versions: