text message truncated in MDI


while editting a TIF document in MS Document Imaging, I entered 10 lines in
textbox (entered an annotation), and Saved Permanently
then the text appearred bold (or larger and does not entirely display) so
permanent message is truncated on my document. I can not always recreate but
sometimes moving the page orientation then entering text box will cause this
scenario. How can I avoid loosing parts of my text in MDI?

.