Using Gemini 2.5 img preview, adding Chinese text to an image in the prompt generates garbled text

gemini 2.5 image preview , image to image . Using English text works perfectly fine.

how i can solve this ?

prompt: The title of the poster is displayed in orange Chinese: “Ai 智能體在企業的應用.” Please ensure that all Chinese text is displayed clearly, without garbled characters, and accurately.

or: The orange Chinese title with the Chinese text ‘Ai Agents 的企业应用’ written on it. Please use UTF-8 encoding for this Chinese title and ensure that it is not garbled.

or : 橙色中文标题为:“AI代理在企业中的应用”。 请以 UTF-8 编码 来处理此标题中文文本,并确保没有乱码。