This is a generic error that is generated when no other error applies. Retry the alert submissions to see if this can be resolved.

Note that some forms require fields that are not default required, e.g. CAPTCHA, phone, county, etc. In those cases, we configure the form submissions so that Luminate Online prompts the constituent for this data. If anything (Luminate Online, the representative's form, etc.) times out when trying to prompt the constituent, the send usually fails with this error. In these cases, there's no way to ask the constituent for that information after the submission is done so re-tries usually fail.