Emails deleted from trash too soon
I'm using Mac Mail on my laptop running OS10.12.3. I set Mail preferences to delete email in trash after 1 month, but only 1 week's worth of emails are in my trash folder. I checked my email online at inmotion and it's the same, only 1 week. I've found a reply from 2013, but I don't think it applies to current versions of IOS and MacOS. I use my iPhone only to view emails, not to delete them. Please advise me how I can keep emails in the trash folder for 1 month.