After 4.6 Update auto translations not showing

Hi,

I just updated to 4.6. I am running an English/Japanese bilingual site. Now parts of the Japanese pages, plugins and posts have stopped being automatically translated. E.g., my-account login, woocommerce, post instructions. Basically anything that was not manually translated using loco translate or polylang. I suspect I need to refresh some core translation files? Not really sure what to do:/

https://www.syncandi.com

Thank you for any help.
Roberto