Date time in discount code detail page is not considering the timezone

[umbracotrd]

Which component is this issue related to?

Umbraco Commerce (Core)

Which Umbraco Commerce version are you using? (Please write the exact version, example: 10.1.0)

16.4.0

Bug summary

The Date range (Start Date/End Date) inputs keep changing with the new value when I keep clicking the save discount button.

Specifics

The Start Date and Expiry Date in the image used to be on 25/10/2025, after few saves, they're reduced to 21/10/2025.

Steps to reproduce

• Set your computer time to GMT +7?
• Start the website locally.
• Go to backoffice > Commerce > Select Store > Discounts > Create discount
• Create any discount with start date/expiry date.
• Click Save discount button several times.

Expected result / actual result

Expect: The start date/expiry date shouldn't be changed after each "save" click.

Actual: The start date/expiry date value are decreased by 7 hours after each "save" click.

Dependencies

No response

[mattbrailsford]

I think this is fixed in v17 as I came across similar. I thought it was just because of the UTC changes in CMS though, but if it's present in the current version we can look to backport it.

[mattbrailsford]

I've cherry picked these updates into the 16.3.3 hotfix branch. We can merge them into the 16.4.0 branch before release (there are some other hotfixes in the branch too)

[mattbrailsford]

16.4.0 has now been released which contains the fix for this issue.