Rows

Hi, I have a Numbers file, 7 sheets in the file and the first is just shy of 500 rows and 11 columns. I usually access it on my MacBook Pro with an M1 chip; software is up to date - Ventura 13.2.1. The problem is that I am currently unable to see the first 110 rows. They are not Hidden; it is more like locked. I can not scroll to rows 2-109. The scroll bar on the right of the window thinks row 110 is the top of the sheet. Right now I can see row 1, a designated header. If I change the headers to 6, I am unable to see rows 5-113. I did the usual of turning the MacBook off and on a couple of times already, but that did not clear the problem.