Using Google Scripts Webapp to get data from a Glide Webhook

So I have a webapp in google scripts. I trigger it with a webhook from Glide.

I need to figure out how to get a value from the webhook.

So in the webapp, once the webhook is triggered, i need to get data from a cell called Job Number, figure out which row that is on, and do something with that row in the script.

What I have in the script:

const content = JSON.parse(e.postData.contents)
const jobNo = content.params.jobNo.value;

let ss = SpreadsheetApp.getActiveSpreadsheet();
let sheet = ss.getSheetByName(“Job Tab”);
let sheetData = sheet.getDataRange().getValues;

I would then check for the row that jobNo is on, so then i could have:

let targetRow = …

It fails every time it runs and I have no idea why.

Is the reason you’re using an Apps Script webapp only because the data you need is stored on another Spreadsheet?