Image generation API hits sometimes return text only

When i am using Nano Banana Pro or Nano Banana 2 i am facing issue with image generation all though i am expecting image plus text output from the api there are maybe 50% cases where the output is only text. I am sending image plus text and expecting generated image plus text. Text output is always generated but image output isn’t always generated. The API response doesnt raise an error. There are no messages like exhasuting tokens per minute or the API is busy etc.