I have created site columns with an prefix (e.g. pre_column1) and then changed the display name to "column1" which works fine for my user and for all user in lists views.
But if some user open the item and the SharePoint form is shown, then they get the internal column names displayed (pre_column1).
The issue seems depending on the browser language. This seems to be a bug because SPO should always show the display column or am I wrong?
When you create a column, its name applies automatically to all site languages. When you change the name of the column, the changed name applies only to the language that you are in at the time of editing (under many but not all conditions).
If you do not want your site to support multiple languages, go to Site Settings, then Language Settings, then Show advanced settings, and uncheck all of the alternate languages and press Save. That way, whatever the language settings of the user, they will see column names and other UI elements only in the base language of the site.
If you do want to support multiple languages but you want your changes to column names to overwrite the original column names in other languages, on that same page change Overwrite translations to On and save. That way any change you make in the base language will be copied to the other languages of the site even if they already have a value.
1.You could try to clear browser cache then restart it.
2.Try to use a different browser or your browser's InPrivate mode to see if the same error occurs.
3.I suggest you can create a new service request in M365 admin center as an admin, and more professional will help you. (Microsoft 365 admin center ->> Support ->> Help & support)
