Edit : to your other comments, it looks like you are re-linking the repeater with every postback. When you do this, you destroy the event ItemCommandsource — the original relay element associated with the button pressed by the client.
"" "" , (postback) BindList() .
, , , "" "".
, :
<asp:Button ID="btnApprove" runat="server" Width="80px" Text="Approve" CommandName="approve"/>
<asp:Button ID="btnDelete" runat="server" Width="80px" Text="Delete" CommandName="delete"/>
: , ItemCommand ? , rpt1_ItemCommand , "" "", , .