ADP Chron’s Rejected

I applied for ADP as i have chrons and struggle with day to day life. However i called and they told me a decision had been made and I have been denied but can re appeal once my letter arrives. I feel let down and disappointed in the system. I know people with far less worst disabilities claiming this. I also know people who have chrons who were approved. Has anyone got advice for my re appeal and if they have done it before please ?