Use it when something physical is preventing movement, often causing annoyance or plans to change. I was late because my car got blocked in by a delivery truck.
Pro Tip 2/3
Asking for Help
You might use the phrase to ask someone to move their vehicle or an object that's causing the block. Could you please move your car? You've blocked me in.
Pro Tip 3/3
Unexpected Delays
Indicates a situation may lead to being late or changing plans, suggesting an inconvenience. Text your boss if you're blocked in; they'll understand the delay.