What are some foods that are easy to bring to work to stay under 20 carbs?

I’m having trouble staying under 20 carbs. All my foods are extremely low but 3 hours into my day I’m already at 7g.

I eat keto truffles in the morning (cause I have no appetite for anything else usually) An avocado after I wake up and gain a appetite And then a handful of walnuts to go with it so my hunger will stop for a while. Recently got some Coke Zero to help fill my belly too.

Any suggestions would be appreciated.