why will the ignore rule for missing capitalization not work

I keep getting the missing capitalization error on my page breaks when an incomplete sentence must continue on the next page. I keep clicking on “Ignore Rule”, but first, it gives me “Spellcheck not responding”, then when I try again, the error is corrected. I’ll save the document to keep the corrections, but when I open it the next time, the error is back. Can anything be done to correct the error permanently?