I NEVER pre-rinse rice. I used to but then I kept coming across online posts (including some from celebrity chefs) saying that it's simply not necessary. I just cook my rice in a saucepan, ensuring that the amount of water matches the rice correctly, so that it's all completely used during the cooking process.
Like others here, I suspect that your rice has been overcooked and/or that you've used too much water. I doubt that there's any solution to the problem. (Sorry!).
However, with a portion of rice costing about 6p, and with it needing less than a quarter of an hour to cook in a saucepan, I can't really see why it should be a major problem for you!