Sending a message to a specific object doesn't work (sometimes)

Whenever I select a specific object to send a message to, the option itself reverts back to “Any Object”, highlighted in gray so I can’t access it. For some reason, this only happens when you label the object with only a number. It’ll work otherwise if you give it more characters.

Scratch that, it doesn’t work if you have two different object types, and both have the same object name.