Excel 2008 : Find merged cells: mac

Working on Excel 2008 for Mac 10.2.2.5

'Find/Replace' doesn't include 'Options' for merged cells. Trying to sort my worksheet, running into "Operation requires merged cells to be identically sized."

I am NOT the creator of the spreadsheet. Has 1900 rows, 28 columns. Have looked, can't find the cells. It's in two columns that have phone numbers entered in too many ways. I will eliminate the merged cells when I find them.

When I try to check/uncheck 'merge cells for these columns, get the message,"Cannot merge overlapping ranges."

Would appreciate your help. If you provide code, please tell me where to enter it as I'm not familiar with using code. Thank you