Help needed.. how to save it? As son as I move to another block it erases.

I am currently paying for the premium.. and I have had many issues in my iOS device.. 

for example I am trying to fill a form on a pdf file.. and everything seems to work when I start typing and how do I save it while I'm moving from block to block.. I type and as soon as I move to another block.. everything disappeared. It's in blue letters and I can adjust the height and length but I can't save it to stay in the block? Any help?