Our site is also affected with Polylang plugin v3.4.3. The problem appeared after changing the URL of the site (without saving changes in homepages).
@velthium, thanks for the workaround!
Thread Starter
sodr
(@sodr)
Hi Becky,
This point did the trick:
Navigate to Settings > Permalinks in your WordPress dashboard and set them to ‘post name’.
Everything else were checked twice before posting here.
Thank you!