Berlin Blockade was another struggle between western powers and communists. It took place in Berlin June 1948 to May 1949. As Germany was split along with Berlin. The instructions came from Moscow to block Berlin that is controlled by West.
The Soviet union blocked all access in And out. This resulted in the West having to fly supplies. This whole event had hundreds of thousands of flights consisted of many nations.
The reasons for the Soviet union to put these restrictions was mainly to weaken the allied influence. The main tipping point was the allies and the Marshall plan.
The Marshall plan was to inject money into Europe (west) to help itself after ww2. There was also a new currency issued to maintain order.