@Yusuf , you could try the following steps to add the dll to use Microsoft Access functions easier.
First, Please add nuget-package Microsoft.Office.Interop.Access.
Second, you can use the namespace:
using Access = Microsoft.Office.Interop.Access;
Third, you could use the following code to use the Dsum function.
Access.Application app=new Access.Application();
app.OpenAccessProject("path");
app.DSum("Credit", "TransactionsDetails", "TransactionsDetails!TransactionsID = " & Me.Parent!ID);
If the response is helpful, please click "Accept Answer" and upvote it.
If the answer is the right solution, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".
Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.