I cannot help with the Russia challenge: "Come back soon when there's more to explore!"

I got to the end of the queue. Is there a hard limit of reviews in a week/month or something like that?
I am pretty sure there are still many reviews pending, probably thousands from Russia (Moscow)
And my Bonus location is India, so im fairly certain i couldnt have run out of reviews from both Russia and India.
Please let me know if there is something i did wrong.
Thank you
Answers
No there is a bug running that stops giving reviews after a certain limit which you can see in the bug report section here : - https://community.wayfarer.nianticlabs.com/discussion/comment/88425#Comment_88425
or that's probably a limit of reviewing I also got it during India Wayfarer challenge which I loved to see that as i did work from myside atleast till some time but as the challenge wasn't completed sadly I wanted to review more to help more from my side. Check the link which would help you out. I had this problem for 4 to 5 days or maybe even more as I don't remember, but it eventually got fixed out after the same duration.