The court reduced the activist’s sentence by one and a half months, taking into account the time he spent under house arrest from December 2014 to February 2015.
Navalny appealed the decision to the Moscow City Court on Saturday.
At the beginning of the proceedings, the anti-corruption activist asked the judge to allow a video recording of the session.
The judge decided not to allow journalists to film the process, but said there would be a “recording of the verdict”.
Olavy’s lawyer Olga Mikhailova then filed a lawsuit against her client for immediate release, as well as the European Court of Human Rights (ECHR).
Mikhailov claimed that Navalny’s life and health were in danger while in custody.
The court made its initial ruling on 2 February after he ruled that while Navalny was in Germany, he had breached the conditions of the probation from a 2014 case in which he was sentenced to three and a half years in prison.
The suspended sentence was then replaced by imprisonment.
Initially, the Russian state arrested Navalny in January after arriving from Germany, where he spent five months recovering from the Novichok poisoning he blamed on the Russian government. The Kremlin has repeatedly denied any involvement.
We will look at the Navalny slander case for comments related to a World War II veteran later on Saturday.