JPG image (2000*2000) consisting one layer saves in 129MB.

[balk634]

Most of the files exhibit this same behavior; they're saving at sizes upwards of 130 MB. To investigate the issue, I began by removing layers, but I found that even when reduced to a blank canvas, the file size remains around 130 MB.

Could you advise on which settings should be adjusted to return the file sizes to their normal values?

[Stephen Marsh · Accepted solution]

Sounds like excessive photoshop:DocumentAncestors metadata. 

Use Export As or Save for Web which strips most metadata.

If you need to use Save As then the links at my blog offer many solutions.

https://prepression.blogspot.com/2017/06/metadata-bloat-photoshopdocumentancestors.html

[balk634]

Quick export as PNG works for me, I will use that from now on. Thank you so much. 

The scripts and other methods contains lot of warnings and couldnt even understand half what's written. I am a newbie.