Ok just in case someoneelse is facing this 13 digits problem:
I installed Redirection Plugin and added the following rule.
Starting url /year/month/post-title/everythingwith13digits
/(20\d\d)[- /.](0[1-9]|1[012])[- /.](.*)[- /.](\d{13})
End url
/$1/$2/$3/
301 Moved permanently