Hi rawaruska,
You can see 2 pages in backward my reply to stephane.schmitt who obtains the same issue.
I had too the same issue due to an error in the french.php file I used.
Modify the initial sentence "You can access to this %s with following %s plans:" by "You can access this %s with following %s plans:" (just suppress "to").
Regards,
Vincimoz