category and tag pages coming up blank?

Hi, i don’t know if this started after i updated to the latest WP version, but just after i did a couple of days ago i first noticed that category pages are not loading at all on my site. Not sure why, anyone have an idea as to that and what to do about it? The rest of the site seems to be fine, posts and pages all load ok. here’s the main link.
https://www.salgoodsam.com/
These are the category links that should work if it were, but come up blank on every browser i’ve tried now.
https://www.salgoodsam.com/section/blog/ch_zero/
https://www.salgoodsam.com/section/blog/
https://www.salgoodsam.com/section/blog/workdiary/
https://www.salgoodsam.com/section/art-3/animation-art-3/
https://www.salgoodsam.com/section/art-3/comics/

Same thing happens with tags.
https://www.salgoodsam.com/tag/dream-life/
https://www.salgoodsam.com/tag/finger-string/
https://www.salgoodsam.com/tag/anthology/
https://www.salgoodsam.com/tag/art/
https://www.salgoodsam.com/tag/audio/
https://www.salgoodsam.com/tag/av/

and so on.
direct links to pages and posts seem fine, but the rest not working?

thanks for your help!
max