This JIRA error means that the value sent from Aha! does not match one of the choices in JIRA.
When creating a custom pre-defined choice field in JIRA and Aha!, then mapping the two, if the choices don't match exactly, you will see this error.
To resolve this issue, double check that your predefined choice list in both Aha! and JIRA match. In particular, look to ensure neither sets of choices contain any extraneous whitespace.