Hi everyone,
We’ve identified a bug affecting forms that use allow_choice_duplicates = true with duplicate choice names. When data is submitted using the duplicate options, the Data tab fails to load, so affected users can’t currently view their submissions.
We’re sorry for the disruption and are actively investigating
If the data needs to be accessed, it’s still possible to generate a downloadable export. You can create one from the Downloads section, and the file will remain accessible even if the Data tab is crashing.
Descripción del error:
Al intentar ver la pestaña “Data” (tabla de datos) de mi proyecto, la
aplicación falla por completo mostrando:
“Unexpected Application Error!
[@mantine/core] Duplicate options are not supported. Option with
value “1” was provided more than once”
Causa identificada:
Mi formulario usa una selección en cascada (cascading select) en la
pregunta “p203” (choice_filter: region = ${p201}), donde la lista de
choices “p203” contiene 31 filas con name=“1” (una por cada valor
posible de la pregunta “p201”), tal como lo requiere este patrón de
diseño en XLSForm.
Ya tengo correctamente configurado allow_choice_duplicates = yes en
la hoja “settings” del XLSForm, por lo que el formulario se guarda y
recolecta datos sin problema.
Sin embargo, la vista de “Data” en la interfaz web (kf.kobotoolbox.org)
falla al intentar construir el filtro/desplegable de esa columna,
ya que el componente Mantine Select no permite valores de opción
repetidos dentro de la misma lista — algo que sí es válido y esperado
en un cascading select con allow_choice_duplicates=yes.
Pasos para reproducir:
Información del proyecto:
Adjunto captura de pantalla del error.
Quedo atento a cualquier información adicional que necesiten para
diagnosticar o confirmar si es un bug conocido.
Gracias de antemano.
@darfo5pestsurvey welcome to the forum, and thanks for reporting this.
We’ve confirmed the issue and are working on a fix. We’ll follow up here as soon as it’s resolved.
I got the same error:
Unexpected Application Error!
[@mantine/core] Duplicate options are not supported. Option with value “Vyshnivska” was provided more than once
Hi @kenmugy @codonob welcome to the forum, and thanks for reporting this.
We’ve confirmed the issue and are working on a fix. We’ll follow up here as soon as it’s resolved.
Buenos días.
Desde hoy estamos presentando un problema en todos nuestros formularios que utilizan allow_choice_duplicates = yes.
Los formularios se diligencian y envían correctamente, pero al intentar visualizar un envío o exportar los datos aparece el siguiente error:
Duplicate options are not supported. Option with value “xxxx” was provided more than once.
Este comportamiento también ocurre en formularios antiguos que no han sido modificados ni republicados, por lo que creemos que se trata de una regresión de una actualización reciente de KoboToolbox.
¿Alguien más está presentando este problema o existe alguna solución?
Adjunto capturas del error.
Same issue. Multiple projects with allow_duplicate_choices set to “yes” are throwing this error.
Data Table crashes with “[@mantine/core] Duplicate options are not supported” on form with cascading selects
Hello KoboToolbox team,
Since around July 15, 2026, the Data tab for my deployed form crashes immediately with this error:
Unexpected Application Error!
[@mantine/core] Duplicate options are not supported. Option with value “dadu” was provided more than once
It also triggers for other values such as “hyderabad_wb”.
Form: Site Supervision progress of Health Facilities (SIHPP 1000 Days) — hosted on kf.kobotoolbox.org
Details:
The form uses cascading/dependent select lists (district and division filtered by contract type), so the same choice name (e.g. “dadu”) intentionally appears multiple times in the choices sheet with different filter values. This is a standard, valid XLSForm cascading-select pattern.
Data collection and submissions work normally. XLS/CSV exports also work. Only the Data Table view crashes.
The form was not modified or redeployed recently — the error appeared suddenly, which suggests a regression in a recent KoboToolbox front-end update.
The stack trace points to the Mantine Select component in the compiled vendors bundle, which strictly rejects duplicate option values and crashes the page because there is no error boundary.
This seems to be the same issue reported in this thread, so multiple users are affected.
Request: Please deduplicate choice values before passing them to the dropdown component, or add an error boundary so one duplicate value doesn’t crash the entire Data Table.
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Happy to provide the XLSForm or more details if needed. Thank you!
I think the issue is cause by a recent update to this file:
TableDropdownFilte
Which is included in the latest release: 2.026.27 from several hours ago.
Issue was created here.
Estimada comunidad, me gustaria saber si ha habido alguna actualizacióno sobre este tema, es bastante complejo, revisando las bases exportadas hay registros que estan saliendo sin el metadado, es decir salen vacios, ¿es posible que sea tambien por ese problema que se esta presentando en el front del servidor?
Hi @LuisB @Isslam @sihpp, welcome to the forum, and thanks for reporting this.
We’ve confirmed the issue and are working on a fix. We’ll follow up here as soon as it’s resolved.
Hi everyone,
Please be informed that the issue has now been resolved. We sincerely apologize for the inconvenience caused.
