What documents do I need to bring to Thai Immigration to pay for an overstay extension?

The user plans to overstay their 30-day visa by 4 days and prefers to handle the situation by visiting Thai Immigration and paying a fine of 1900 THB to avoid an overstay stamp on their passport. They inquire whether they need additional documents from their hotel aside from their passport copy and airline tickets. A comment suggests going to Thai Immigration to apply for a 30-day extension and mentions the necessity of ensuring the TM30 form was filed by the hotel during check-in.