Does this same behavior arise in other surveys? First thought was your theme has a bug, but if you create another survey, add a slider question, and see the correct behavior, I'd say your survey has a bug and could be corrupted. Sometimes copying the survey will fix it, sometimes I've had to rebuild surveys that had similar bugs/weirdness.

https://community.qualtrics.com/XMcommunity/discussion/comment/41504#Comment_41504hi - yes it does the same in other surveys.
Apparently Qualtrics have advised that this is an issue with the dynamic themes and that using a static theme will fix it. Also, slider questions are being phased out so there seems to be little enthusiasm to fix it at their end.

Yeah, that's a shame. Your 0,25,50, etc is called the label-slider. It looks like its smashed into your slider-containers. I would probably try a solution where you grab the slider-container class (they'll be one for each slider) and move them all down a specific amount of pixels until they line up with your statements. Since this is happening for every slider question across the board, I would either A) Add the CSS to your theme or second best would be add the solution to the CSS in every survey that utilizes slider questions.