When looking at coordinates on the F3 screen, there is both a 0 and -0. (Positive zero and negative zero)
Even though they shouldn't exist, realistically, this isn't a problem. However /tp [user] -0 ~ -0 teleports to 0,0 instead of -0, -0.
Linked issues
Comments 2
See MC-36602.
Please attach a screenshot with the debug menu saying -0.