Dear webmaster,
We have noticed that on a number of the pages on your site the rel-alternate-hreflang implementation is incorrect. For example:
In particular, there seems to be a problem with missing or incorrect bi-directional linking (
when page A links with hreflang to page B, there must be a link back from B to A as well). When our algorithms detect conflicting signals like on these pages, they may make indexing and ranking decisions that do not match what you intended.
To learn more about rel-alternate-hreflang, see the following Help Center article:
https://support.google.com/webmasters/answer/189077
If you have any questions about how to resolve this issue, please visit our Help Forum:
Google Groups
Sincerely,
The Google Search Quality Team