after applying localization with RadSchedulerLocalizationProvider on radScheduler, the returned value of reminder was wrong.
for example the "5 minutes" changed to "5 hours" in my database.
in greek "5 minutes" is "5 λεπτά"
applied culture is set to "el-GR".
The issue that you described is not reproducible on my end. You can refer to the following help article concerning how to localize RadScheduler to display control text and messages in a specific language: https://docs.telerik.com/devtools/winforms/controls/scheduler/localization/translating-strings.
However, if you are still any further difficulties I will kindly ask you to provide a project where the issue occurs. Thus, we will be able to investigate the precise case and assist you further.
If you have any questions, please do not hesitate to contact us.