A lady showed up in my DNA I think they are the same person. The first one showed up as 1,942 centimorgans shared across 72 DNA segments. The 2nd one says 936 centimorgans shared across 36 DNA segments and it says she is managed by the 1 st one.. What does this mean?
They are not the same person - the DNA for the two results are very different, so much that one shares roughly twice as much DNA with you as the other person. When a DNA testing site says one person's results are managed by another person, it means that the person who was tested and the person who logs in to the web site are two different people. For instance, a person had their child or elderly parent get tested, the latter person might not use the web site.
You can see a list of likely relationships for the person who matches 1,942 cM here:
https://dnapainter.com/tools/sharedcmv4/1932. That page says that the relationship is almost certainly one of these: "Grandparent Aunt / Uncle Half Sibling Niece / Nephew Grandchild"
And for the other person here:
https://dnapainter.com/tools/sharedcmv4/934. The relationship to that person is almost certainly one of these: "Great-Grandparent Great-Aunt / Uncle Half Aunt / Uncle 1C Half Niece / Nephew Great-Niece / Nephew Great-Grandchild".
The hypothesis in the comment by Marshall Clow that the first person is the parent of the second seems possible. For instance, the first person could be your half sibling, and the second one could be their child, which makes them your half-niece/half-nephew.