Edit, Save, redirect

I am drawing a blank on this URL Formula.
I am in the record's form and have a custom URL Formula button.
When clicked, I need it to edit a field in that record, save, then redirect to the parent record in view mode.

The code I have been using is the following:

var text EditAssignment = URLRoot() & "db/" & Dbid()
& "?act=API_EDITRecord&rid=" & [Assignment ID#]
& "&_fid_157=" & "1";

var text DisplayParent = URLRoot() & "db/" & Dbid() & "?a=dr&rid=" & [Assignment ID#];

$EditAssignment
& "&NextURL=" & URLEncode($DisplayParent)


However, I get an error message. I have tried changing the second [Assignment ID#] to the [Related Job], as well as [Job ID#], but neither takes me back to the parent record.

FYI, [Job ID#] is the unique record ID field for the parent record.

What am I getting wrong in my formula?

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Andrew
andrew.fry25@gmail.com
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