I'd guess you need to go in from the front and add a new bookmark. If this doesn't work just go in the front all the time. It is good practice to keep albums to a reasonable size by starting new ones from time to time, ie new sub-albums within your main album.
I don't have to go to the site because it can be done through the Photobucket android app, which is much easier to use. Pics appear in date sequence as pics-without-names, and there is no risk of names clashing because Mr Bucket assigns his own unique name to each pic.
Hope this is helpful.
