Unique iPhone Name still adds (#), and the (#) is ever increasing

I have named my iPhone a unique name, and can 100% guarantee that there are zero devices that share my home and/or work networks that have the same name -- and yet, without fail, as I move from home to work to home again (and therefore back and forth between those two WiFi networks), a (#) will appear at the end of my iPhone's name. So "Unique iPhone Name (3)" -- and if I do not reset the name manually back to "Unique iPhone Name", when I get home it will have increased to "Unique iPhone Name (4)" etc. etc.

This wouldn't really bother me, except that now I can see the ever-increasing numbers on my lock screen's battery widget and my bluetooth devices announce the full "Unique iPhone Name (4)" including the number, and its extremely annoying. Any advice appreciated!