Anyone have this problem when eating peanuts

Tonight I went to Logans was some friends. I checked my blood sugar and it told me I was 339. Now my CGMS is set to tell me when I hit 120 and it hadn’t been going off, I even checked to make sure I didn’t miss any alarms. I had been drinking water all day, had no sugary substances on my hands. I had checked my sugar about 4 hours before that and I was 134 with 1 unit of active insulin in me and I had eaten nothing after I had came in at 134, I felt fine, no illness. So I went to wash my hands came back and rechecked 99, I checked one more tonight just to be safe and was 99. So I don’t know if it was fluke, or if I had something on my fingers.
And oh yea I checked my sugar about an hour after eating and was under 100 so I had a small mini bucket of cheesecake. Just enough to give myself a treat, but not enough to sky rocket my blood sugar. I am know sitting at a pretty 117. Gotta love it when you can spoil yourself every once in a while. And I got asked by the waitress “Can you eat that?” when she saw my pump. And my friends came to my rescue and told them that I have excellent control and I can eat what I want.

Sounds like you probably had something on your finger when you tested. That would be the only thing that I could think of that could cause that type of a dramatic difference, particularly without your CGM going off.