Tips for filing claims without proof of purchase

Most people don't realize that "no proof required" means you just self-certify you bought the product. Here's what I've learned after filing 20+ claims: (1) Use a dedicated email so you don't miss confirmation emails. (2) Screenshot your submission — some administrators ask for it later. (3) The deadline is usually firm, but the payout date isn't — set a calendar reminder for +12 months. What tips do you have?