I've had problems with a 5G provider dropping pings with smaller than usual payload sizes, like those sent by dpinger by default. One thing to try is setting your ping payload size to 56 bytes so it looks like a normal ping.
To change this setting in OPNsense go to System: Gateways: Configuration, edit your gateway, switch on "advanced mode", and change Data Length to 56.
			To change this setting in OPNsense go to System: Gateways: Configuration, edit your gateway, switch on "advanced mode", and change Data Length to 56.
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