Eyedropper bug — attribute pick-up is glitched by hidden layers above
If there are objects overlapping and above the source for the eyedropper tool, — even if those objects are on a hidden layer — the tool picks up a color of no fill and no stroke.
If the hidden layer is dropped below the target layer, the problem goes away.
These observations are based on original input by Bill Silbert in this User Forum discussion:
InDesign versions v14 through v15
We need more information to reproduce this issue. Could you share a sample test document and show a screen recording of this issue?
Adobe InDesign team