Answer:
The Provisional government lost the support of the people and the army.
Step-by-step explanation:
The communists succeeded in overthrowing the Provisional Government in the November 1917 Revolution because the Provisional government lost the support of the people and the army.
The Provisional Government in Russia was established on 17th March 1917 after the abdication of Tsar Nicholas II. Soon after its establishment there was steady and systematic disorganization of army and it lost the support of people as well as of army. That is why it was overthrown by communists in the November 1917 Revolution.