When dialog box is displayed no head text is shown for SFdropdownlists. It is displayed on the datagrid grid.
Example of one gridcolumn
<GridColumn HeaderText="STATUS" Field="@nameof(CalibrationTask.status)"
Width="150" DefaultValue="@("Not Started")" EditType="EditType.DropDownEdit" ><EditTemplate>
<SfDropDownList ID="StatusName" TItem="Status" TValue="string" @bind-Value="@((context as CalibrationTask).status)" DataSource="@Statuses">
<DropDownListFieldSettings Value="StatusName" Text="StatusName" ></DropDownListFieldSettings>
</SfDropDownList>
</EditTemplate></GridColumn>