Uniper was forced to use emergency supplies after Russia stopped natural gas deliveries to the country.
According to a Financial Times report, the Dsseldorf-based company, which is Europe's biggest buyer of Russian gas, has been taking gas from storage units.
The company has had to rely on its emergency winter supplies to meet contractual obligations due to the fact that it hasn't received any supplies from the Nord Stream 1 line.
Germany has been forced to accept only a small amount of gas from Russia, which has worsened the country's energy crisis.
Germany's Federal Network agency said that this development makes it harder to reach the storage levels necessary for the winter and reduces the reserves available in the event of a gas deficit situation.
Germany wants to refill the gas storage facilities by the end of the year. The shortages could hurt other European nations like France, Austria, and the Czech Republic.
There are safety warnings and maintenance issues that may cause a delay in gas deliveries to Germany.
The analysts at Goldman said last week that the gas exports would remain low if the repairs were not done quickly.
Since the beginning of the war in Ukraine, German officials have been working on a rescue for Uniper. The government is likely to take a stake in the utility giant after the company requested a rescue package.