This is usually tied to how Lightroom hands the file to Photoshop and how Lightroom treats the returned file.

A key setting is the Edit In choice: if Lightroom asks whether to edit the original, a copy, or a copy with Lightroom adjustments, choose the option that preserves Lightroom adjustments.

Also, Lightroom may reasonably discard Develop settings if Photoshop changes the image in a way that invalidates them, especially if the image dimensions change. In normal round-tripping, Lightroom should usually preserve your adjustments, so if this is happening without size changes, it may be a Lightroom/Photoshop bug or regression that some users have seen more often in newer releases.

How to reduce the issue:

• Use the correct Edit In option that includes Lightroom adjustments.
• Avoid changing canvas size or dimensions unless necessary.
• Keep using History or Snapshots as a safety net.
• If PSDs don’t trigger the problem in your setup, using PSD instead of TIFF is a practical workaround.