Certain text not going onto signs

When playing on a very dense, super flat realm of mine I attempt to write down a sign that says "00.00." This works while I am writing the sign, but as soon as I press "B" on my Xbox One Wireless Controller as to stop writing, and have the sign be finished, the text disappears.  Inputting any other digit in place of the 0's also results in the same issue. I have tried going to different parts of the world, turning my render distance down, turning my anti-aliasing down, and more, but it still will not work properly. Other players can write down all of their signs perfectly, but I cannot. I have also tried getting rid of plenty of signs on the realm, but it still will not work. One thing that did work was getting on an actual, normal version of the world that was downloaded before the world became a realm, so I am guessing that this glitch is due to the realm feature.