How do I change my maximum review interval?
On the desktop version, click on the cogs icon of any of your decks and press Options. Scroll down to Advanced and set the Maximum interval to whichever number of days you would like. I usually like to have it as being 60 days.
You don't have to repeat this process for all your decks as you will notice on top, it says that
Default (used by X decks) as the preset so will apply to all decks which are tied to that preset (which should be all of them).