If you have used LIMS-plus before v3.8, you are used to always seeing your requests ordered by request number. In v3.8, the request grid now has "smart columns" that allow you to sort the list any way you like. Just click the column title to sort the rows by that column.
The column with the up or down arrow next to the title (1) shows you how the list is being sorted. If you find your requests are no longer ordered by request number, just click the title of that column (2) to re-sort them.