Storage: getItem() method

The getItem() method of the Storage interface, when passed a key name, will return that key’s value, or null if the key does not exist , in the given Storage object.

Storage: getItem() method - Web APIs | MDN (mozilla.org)

With the above information on getItem() , maybe you have to setItem() the key/value pair first before you “get” them.

Storage: setItem() method - Web APIs | MDN (mozilla.org)