What is the common cause of "The prefix has already been used" error

[verynewuser]

After renaming an integration test in my .NET solution, I started receiving this exception:

System.Exception : The prefix has already been used: C:\companyName\Repositories\solutionName\tests\Comp.Proj.IntegrationTests\Cities\CitiesTests.ListCities_Succeeds.
This is mostly caused by a conflicting combination of `VerifierSettings.DerivePathInfo()`, `UseMethodName.UseDirectory()`, `UseMethodName.UseTypeName()`, and `UseMethodName.UseMethodName()`.
If that's not the case, and having multiple identical prefixes is acceptable, then call `VerifierSettings.DisableRequireUniquePrefix()` to disable this uniqueness validation.

[verynewuser]

I got it myself. Without paying attention to the consequences, I was trying to call Verifier.VerifyJson(rawResponse.Json) in a loop for an API call, and on every call it was trying to generate a new file with the same name.