Thank you very much for your help.

I ran the QB Print & Repair Tool as you said, I also ran the Quick Fix my Program and the QB Program Diagnostic Tool under the "Program Problems" tab along with the Run QB File Doctor under the "Company File Issues" tab. The result was that found no issues and I still don't have the register lines on my current company file.

I really don't know what it is but as I said, on the new company file that I created as a test I have the register lines (please see image bellow). Unfortunately this new company file has no data. All my data is on my current company file (an image for it is attached as well).