System.InvalidOperationException: The accumulator does not yet have enough entropy to generate data.

[RSkhirtladze]

I encountered an issue when calling the GetBytes method in the Fortuna.PRNGFortunaProvider class. The following error is thrown when I invoke the method consecutively from multiple threads:

System.InvalidOperationException: The accumulator does not yet have enough entropy to generate data.
at Fortuna.Accumulator.FortunaAccumulator.GetRandomDataFromPools()
at Fortuna.PRNGFortunaProvider.GetBytes(Byte[] data)

Steps to Reproduce:

• Create a multi-threaded application with, for example, 10 threads.
• Create _random = PRNGFortunaProviderFactory.Create(token);
• In each thread, call the _random.GetBytes method 10,000 times consecutively.
• Run the program.
• Observe the System.InvalidOperationException.

Observed Behavior:

The error occurs consistently when GetBytes is called from multiple threads simultaneously.
When the method is invoked consecutively in a single-threaded context, it works without any issue.

The GetBytes method should either be thread-safe or explicitly document that it is not thread-safe.
Is it supposed to be thread-safe?
Why does the error occur specifically when calling the method from multiple threads, but not in single-threaded scenarios?
What changes or precautions should be taken to safely use GetBytes in a multi-threaded environment?