Keynote equation export to PDF shows different

I am writing an equation with an absolute value:

d(c,x)=|c_1-x_1|+|c_2-x_2|

In Keynote, it looks good: ![Screenshot of the Edit Equation window inside of Keynote with the equation rendered properly with the absolute notation ][1] But when I export to PDF, the equation becomes ![Screenshot of the same equation in a PDF but the absolute notation is not rendered ][2] (absolute notation is not rendered). I am using Keynote version 13.2 (7038.0.87). Does anyone have the same issue?