Am having this account error while trying to submit a sales invoice. It is only for this particular customer.I have compared with the other customers and everything seems to be ok.
Unfortunately that message is too general to resolve this
Unless someone has more insight, here are two ideas - but these require server access and some code level skill
in the database, compare tabCustomer entries for clues to what may be amiss with that one entry - say a blank field or a character encoding issue
in the save_doc code, set a break point - for eg import ipdb; ipdb.set_trace() - to pinpoint the code where the message is thrown.
I did a frappe update and restarted the server and luckily the error was fixed.