Non-existant extension ringin into my remote extension

I have a FreePBX 11 system with one remote extension at my home (Yealink T-28). I am getting repeated calls from extension 202 to my remote extension at home. But there is no extension 202 on the FreePBX system. Also, there is no record of 202 in the CDR on the FreePBX system. And no one is on the other line (at least, that I can hear). How do I stop these random calls, that happen over and over again, to my remote extension at home? Is this a problem with my home router or the configuration of the Yealink phone?

Try Enabling the Accept Sip Trust Server Only option.