[Koha] Lost password

Sir/Madam, I have upgraded to 18.05 unfortunately, to remove auto increment, I deleted borrowers and old issues. after that, I am trying to open koha with my Id and password but not accepting. In old version (17.11), It was remain stored in xml file and with user ID koha_library and password we were able to recover it. But now what to do? Kindly guide me. Rajesh Bhatt