registering a new billing acount

When I want to register a new billing acount the title gives no normal response.
It says HIKA_TITLE_MR in stead of just mr. This is with all titles

How can I change that?

That's because you have an out of date translation file.
Either update your translation file via the interface in the Languages tab of the configuration
or edit the title custom field via the Display->Custom fields menu and change the texts of each choice.