did you read https://sbqr.ru/standard/files/standart.pdf?

it's required fields that should not exceed 300, not optional + required
https://github.com/codebude/QRCoder/blob/cecf2066d3f3a74b142aaa7c8d9f744c4673118c/QRCoder/PayloadGenerator.cs#L2531

please fix asap