Changing colors on signs (Formatting?)

I apologize in advance about the description. I am not the greatest at explaining things nor really understand which version of MC this bug affects.

To get to the point, friends and I share a realm, and when attempting to use the section sign (§) and an assigned color, the color and section sign disappear, restarting the sign to default font and coloring. First it occurred with the spruce, then we tested it on other signs that were previously changed. The signs that were already changed before stayed the same. But new signs kept reverting back to default.