I’m trying to set up an automated workflow using Zapier where PayPal acts as the trigger and Firebase serves as the action endpoint.
My Setup:
Trigger: PayPal payment events
Action: Firebase database operations
The goal is to automatically execute Firebase actions whenever a successful PayPal transaction occurs through Zapier.
Current Progress:
Zapier generated a webhook URL like https://hooks.zapier.com/hooks/paypal/?cid=1638056 which I configured in PayPal’s IPN settings. The connection test shows successful integration with PayPal.
The Problem:
When testing the automation using PayPal’s sandbox webhook simulator, I select “payment completed” events and hit send. The system displays “Your response is in queue” but the Zapier action never triggers.
Has anyone successfully configured this type of PayPal to Firebase automation through Zapier? What might be causing the webhook events to queue instead of processing immediately?
That queuing usually means Zapier’s failing webhook validation. PayPal IPN is picky about response codes and timing - Zapier often can’t keep up. I’ve hit this same issue before. The problem? Zapier’s webhook handler isn’t sending back the right HTTP status code fast enough. PayPal wants a 200 response within 20 seconds or it queues the notification for retry. Skip IPN entirely and use PayPal’s REST API webhooks instead - they’re way more reliable with third-party services. Set up the webhook directly in your PayPal developer dashboard and point it to Zapier’s URL. REST webhooks handle errors better and don’t use the old IPN system. Also double-check that your Zapier trigger matches PayPal’s webhook format. IPN and REST webhooks have different payload structures, which might explain why your automation isn’t triggering despite successful delivery.
Yeah, this is super common with PayPal’s IPN system. I’ve dealt with this before - it’s usually webhook authentication failing between PayPal and Zapier. PayPal’s IPN needs specific verification steps, and Zapier doesn’t always handle them consistently. Turn on detailed logging in Zapier’s webhook settings first. You’ll see exactly what happens when PayPal sends the notification. Also check your Firebase action - make sure it’s mapped correctly for PayPal’s IPN data structure. If the field mapping between PayPal’s payment data and your Firebase fields is off, the whole thing fails silently. Skip the simulator and test with a real sandbox transaction instead. Actual payment events include extra verification data that makes everything work better.
Had this exact problem building payment processing for an e-commerce client. PayPal’s IPN verification clashes with how Zapier handles webhooks. PayPal sends the notification but wants your endpoint to verify it by posting the same parameters back to their verification URL. Zapier doesn’t do this verification automatically, so PayPal thinks the webhook failed and keeps retrying. You’ll need a custom webhook in Zapier with IPN verification built in, or create a middleware endpoint that handles PayPal’s verification before it hits your Zap. The sandbox simulator skips key verification steps that real transactions have - that’s why actual sandbox payments work better than the simulator.
check zaps settings, likly the payload format from paypal ain’t matching what zap expect. i switched to paypal’s new webhook system, it’s way smoother in my experince.
I’ve built dozens of payment automations and PayPal’s IPN system is a nightmare with Zapier. The queuing happens because Zapier can’t handle PayPal’s strict webhook requirements properly.
PayPal expects immediate responses and specific validation. Zapier adds too much processing overhead, causing timeouts that trigger the queue system.
I switched to Latenode for all my payment workflows after dealing with this exact problem. It handles PayPal webhooks natively without the timing issues.
The Firebase integration is seamless too. You get real-time webhook processing without the delays that break PayPal’s IPN flow.
Built a similar setup last year for a client - PayPal transactions update Firebase instantly. No queuing, no mysterious failures.
Latenode’s webhook debugger shows you exactly what PayPal sends, so you can fix mapping issues immediately instead of guessing.
i had that issue too! it’s kinda annoying, but real payments work better than the simulator. just do a test payment in sandbox and it should trigger the zap. good luck!
PayPal’s simulator is flaky with webhooks - I’ve hit this exact issue building payment flows.
Zapier sucks at handling complex webhook scenarios. The queuing problems come from timing delays or payload formatting issues between PayPal and Zapier.
I dumped Zapier for Latenode after dealing with this crap too many times. It handles PayPal webhooks way better and connects to Firebase without the weird delays.
Latenode’s got proper webhook debugging so you can actually see what PayPal’s sending. The Firebase integration doesn’t have Zapier’s wonky trigger issues either.
Built this exact workflow last month - works perfectly. No queuing, no mysterious delays.
zapier’s webhook timeout is probably to blame. paypal ipn demands quick responses, but zapier can lag, causing that queue. try turning on webhook retries in your paypal dashboard - usually sorts the delays out.