Hello, I have a problem with the font of the title blocks in the drawing that a client sent me. I don't know why, but the fonts and size of the text change by themselves. How is that possible? I don't understand. I open the template he sent me and that simple action have all the texts changing. Can someone help me?

At first, I didn't have the font installed in Windows, so I looked for it and installed the font, but the problem remains.