Posting Payments in Wild Apricot using the generic API call

This is the first time that I am trying to post payments to invoices in Wild Apricot using the generic API module.

I’m hitting a roadblock and cannot see what my issue is, I’m getting an error when attempting to post a payment. The message is:
The operation failed with an error. Your request was invalid: . null

Here’s a look at the very basic setup used to test a post to an invoice. The first two modules work and return the appropriate data.

Here’s the body in the module:

Here’s the error I’m getting:

Thank you, Dan

Your JSON is invalid.

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module-1-input-bundle.txt (12.3 KB)


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Thank you!

After looking at the code in json formatter, it took just a few seconds to figure out what was going wrong with my code.

What I did to get to the bottom of it, after getting a clue from the formatter, I just hard coded all the values in the code for the post. When I did that, the payment was successfully posted. I then methodically went through each variable, adding one at a time, testing the method each time till one failed.

It turned out that the URL variable from the previous module, 4.Url below, needed to be surrounded in double quotes. Once I made this change, it worked.

“Value”: 351.75,
“DocumentDate”: “2024-05-08”,
“Invoices”: [
“Id”: 4.Id,
“Url”: “4.Url”
“Contact”: {
“Id”: 4.Contact.Id,
“Url”: “4.Contact.Url”
“Tender”: {
“Id”: 2636311,
“Url”: “
“Comment”: “Test Comment”,
“PublicComment”: “Test Public Comment”,
“PaymentType”: “InvoicePayment”


Hello there @DanSanders :wave:

Amazing to hear that you were able to get rid of your problem with assistance from @samliew! Thank you for posting here the final solution. We appreciate it. :rose: