If the spots stay in the same place from shot to shot and don’t change when you switch lenses, the issue is most likely dust or debris on the camera’s sensor/filter, not the lens.

These marks can be more visible in some photos than others, especially depending on subject and aperture. A few spots can sometimes be corrected in post-processing, particularly from RAW files, but that’s only a partial fix.

The proper solution is sensor cleaning. You can:

• use the camera’s built-in sensor cleaning function if available
• clean the sensor carefully yourself using proper sensor-cleaning methods/tools
• have a camera service center or repair lab clean it for you if you’re not comfortable doing it

Whether it’s dust or possibly oil, the key clue here is that the spots are fixed in the image position, which points to contamination inside the camera rather than a problem with a particular lens.