When you say 'Text 4', is that PRJ_RESOURCES.prUserText4 (aka Resources), or INV_PROJECTS.prUserText4 (Aka Projects).
Both Resources and Projects are also linked to Financial set-up (aka Financial Department) which aligns to the error message you have posted.
Are you able to edit the Project/Resource (eg change their name), to see if this type of update causes the same type of error. You may be hitting a generic issue, rather than one specifically relating to prUserText4 which in both cases, should just be a string/char attribute.