SharePoint 2016 – Error when inserting a BDC webpart

We are running SharePoint 2016, and up until now have had no problems with Business Data Catalogs. Now when I try to access a page that has a DBC webpart on it I get this error and the page won’t load at all:

Server Error in ‘/’ Application.

Parser Error Description: An error occurred during the parsing of a
resource required to service this request. Please review the following
specific parse error details and modify your source file

Parser Error Message: Index was outside the bounds of the array.

Source Error:

Line 1: <%@ Register TagPrefix=”cc1″
Assembly=”Microsoft.SharePoint, Version=, Culture=neutral,
PublicKeyToken=71e9bce111e9429c” %><cc1:BdcDataSource runat=”server”
LobSystemInstanceName=”ace_reporting” EntityNamespace=”http://xxx/xxx”
EntityName=”BOR_WP1″ EntityId=”0″ Enabled=”True”
ShowSampleData=”False” SelectCommand=”” InsertCommand=””
UpdateCommand=”” DeleteCommand=””></cc1:BdcDataSource>

Source File: /SitePages/Dashboards.aspx Line: 1

——————————————————————————– Version Information: Microsoft .NET Framework Version:4.0.30319;
ASP.NET Version:4.8.4261.0

I even tried to add a brand new BDC webpart to an existing page that has nothing on it, and when I click to insert the webpart I get this error:

“Index was outside the bounds of the array”

I reset the BDC service from Central Admin and no change. Like I said everything was working fine yesterday, any suggestions? Thanks.