What should I do if my 90-day report date at Chiang Mai immigration is incorrect?

l Went to immigration in Chiang Mai to do my 90 day drive thru today and I think they made a mistake. They put my next report 2 months from now instead of 3, I didn't notice till later. Plus they gave me back the form I have to give stapled to the old paper and with the old date crossed out and the new report date written with a fluorescent highlighter pen. I'm confused. I saw the car in front get the same papers given to them and I thought they had made a mistake and they had to go back but now I don't know what to think or do . Any ideas? Thanks.