Value relation dropdown issue -Dropdown list selection reverts to default value upon selecting subtype option

[vishnunv2696]

What is the bug or the crash?

There is an issue with the attribute form value relation. The dropdown list setup is working, but when a subtype option is selected, it automatically reverts to the default value instead of retaining the selected option. This issue persists across different samples when I tested.

Steps to reproduce the issue

test_value_relation.zip

Versions

QGIS version 3.36.0-Maidenhead QGIS code revision 09951dc0 Qt version 5.15.3 Python version 3.9.18 GDAL/OGR version 3.8.4 PROJ version 9.3.1 EPSG Registry database version v10.098 (2023-11-24) GEOS version 3.12.1-CAPI-1.18.1 SQLite version 3.41.1 PDAL version 2.6.0 PostgreSQL client version 16.1 SpatiaLite version 5.1.0 QWT version 6.1.6 QScintilla2 version 2.13.4 OS version Windows 10 Version 2009

Active Python plugins HCMGIS 24.1.12 qfieldsync v4.9.1 qgis-plugin-findreplace-main 1 QuickOSM 1.17.1 quick_map_services 0.19.33 quick_search 1.2 searchlayers 3.0.16 db_manager 0.1.20 MetaSearch 0.3.6 processing 2.12.99

Supported QGIS version

• [ ] I'm running a supported QGIS version according to the roadmap.

New profile

• [ ] I tried with a new QGIS profile

Additional context

No response

[elpaso]

Can you add a short video? I Cannot reproduce on current master.

[vishnunv2696]

https://github.com/qgis/QGIS/assets/173331997/fbde3ba5-5dc0-46fa-94cd-8570d71009fb

[elpaso]

Thank you, it wasn't clear that you were using the attribute table: it works fine from the form.

[vishnunv2696]

The form is working, but the end result in the attribute table shows different values. I already mentioned the problem of selection in the video and we are facing the same issue in the QField survey.