DNN 5.6.5

Module: 4.36

When clicking on "Manage Payments" and if I click on "Cancel Subscription" the following error occurs:

AssemblyVersion: 5.6.5
PortalID: 0
PortalName: Local Livin' Ads - Local Classifieds, Local Prizes, Local Chatrooms, Local Events, and more!
UserID: 1
UserName: host
ActiveTabID: 486
ActiveTabName: BD Customer Manager
RawURL: /Admin/BDCustomerManager/tabid/486/ctl/ManageSubscription1/mid/1976/Default.aspx
AbsoluteURL: /Default.aspx
AbsoluteURLReferrer: https://locallivinads.com/Admin/BDCustomerManager/tabid/486/ctl/ManageSubscription1/mid/1976/Default.aspx
UserAgent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_7_3) AppleWebKit/535.11 (KHTML, like Gecko) Chrome/17.0.963.79 Safari/535.11
DefaultDataProvider: DotNetNuke.Data.SqlDataProvider, DotNetNuke.SqlDataProvider
ExceptionGUID: 3a54b91d-dec6-425e-a9fb-4daea71301ed
InnerException: Input string was not in a correct format.
FileName: 
FileLineNumber: 0
FileColumnNumber: 0
Method: System.Number.StringToNumber
StackTrace: 
Message: DotNetNuke.Services.Exceptions.PageLoadException: Input string was not in a correct format. ---> System.FormatException: Input string was not in a correct format. at System.Number.StringToNumber(String str, NumberStyles options, NumberBuffer& number, NumberFormatInfo info, Boolean parseDecimal) at System.Number.ParseInt32(String s, NumberStyles style, NumberFormatInfo info) at System.Convert.ToInt32(String value) at Smith.DNN.Modules.Registration.ManageSubscription1.CancelSub(DataGridCommandEventArgs e) at Smith.DNN.Modules.Registration.ManageSubscription1.DataGrid1_ItemCommand(Object source, DataGridCommandEventArgs e) at System.Web.UI.WebControls.DataGrid.OnItemCommand(DataGridCommandEventArgs e) at System.Web.UI.WebControls.DataGrid.OnBubbleEvent(Object source, EventArgs e) at System.Web.UI.Control.RaiseBubbleEvent(Object source, EventArgs args) at System.Web.UI.WebControls.DataGridItem.OnBubbleEvent(Object source, EventArgs e) at System.Web.UI.Control.RaiseBubbleEvent(Object source, EventArgs args) at System.Web.UI.WebControls.Button.OnCommand(CommandEventArgs e) at System.Web.UI.WebControls.Button.RaisePostBackEvent(String eventArgument) at System.Web.UI.WebControls.Button.System.Web.UI.IPostBackEventHandler.RaisePostBackEvent(String eventArgument) at System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument) at System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData) at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) --- End of inner exception stack trace ---
Source: 
Server Name: D132