[Koha] Error on patron login if borrowed a book

Hello, I am a new Koha User. Currently I have upgraded the vesrsion to 2.9. And I've been able to manage the technical issues of the system very well. But now, there seem to be a problem on this version of Koha, i.e Patrons are not able to check their borrowed(issued)books through their profile unless the book that they have borrowed is returned. The error message " Error Login" will appear when a patron who has borrowed a book tries to login. But once the book is returned, then it allows the patron to login. Can you please provide me some help? Thanks.