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Best answer

Sub-zap retries due to throttling and fails with "We expected callbackUrl to be stored!"

  • June 28, 2025
  • 6 replies
  • 83 views
S

I have a scenario where multiple Zaps call a sub-zap that does some data processing and calls QuickBooks Online “Create Sales Receipt” step. Sometimes the sub-zap fails on QBO step with the following error:

Too many Zaps trying to access the same resource at the same time. It will be retried after 15 seconds

The sub-zap logic eventually succeeds, however it fails with the error:

Did you fork or replay this step? We expected callbackUrl to be stored!

I assume that the callbackUrl gets lost during the retry due to the retry. Has anyone figured a way to work around this?

Best answer by SamB

Hi ​@stankovski! 👋

Just came across this and wanted to check how you’re getting on. Did iklionjon’s reply help you to get things solved?

If not, does the Zap have Paths with more than one Return from Sub-Zap action in the Zap?

If it does, then according to this help guide on Sub-Zaps, it’s expected that you’d see that error:

5b7aa48de5da28c436399c2fe98a0dd9.png

You’d need to ensure that the paths run are set to use sequential execution.

Keep us posted on how it’s going, want to make sure you’re all set! 🙂

This post has been closed for comments. Please create a new post if you need help or have a question about this topic.

6 replies

J
  • jiklionjon
  • 1 reply
  • June 28, 2025

Same here — retry drops the callbackUrl, likely due to Zapier’s retry logic; splitting or delaying sub-zap calls helped in my case.

  • Faced same issue with sub-zap retries
  • Zapier drops callbackUrl on retry
  • Fixed by spacing out triggers (e.g., 10–15 sec delay)
  • Also split traffic into multiple smaller Zaps
SamB
Community Manager
Forum|alt.badge.img+11
  • SamBCommunity Manager
  • Community Manager
  • 9736 replies
  • Answer
  • July 9, 2025

Hi ​@stankovski! 👋

Just came across this and wanted to check how you’re getting on. Did iklionjon’s reply help you to get things solved?

If not, does the Zap have Paths with more than one Return from Sub-Zap action in the Zap?

If it does, then according to this help guide on Sub-Zaps, it’s expected that you’d see that error:

5b7aa48de5da28c436399c2fe98a0dd9.png

You’d need to ensure that the paths run are set to use sequential execution.

Keep us posted on how it’s going, want to make sure you’re all set! 🙂

S
  • stankovskiBeginner
  • Author
  • Beginner
  • 5 replies
  • July 14, 2025

Thanks ​@jiklionjon for sharing, I’m also trying to increase the delay before the requests to avoid these errors altogether. But I’m still curious what the right solution is for error handling.


Hi ​@SamB, thanks for the reply. I do have a fork in code that has 2 returns from sub zap. It’s a fork based on the error in the QBO action. If it fails I want to send an email and if it succeeds I exit the sub zap. Is the recommendation not to have a return from sub zap as part of the error flow?

Edit: just checked the link you have shared about sequential execution. Will give it a try. 

SamB
Community Manager
Forum|alt.badge.img+11
  • SamBCommunity Manager
  • Community Manager
  • 9736 replies
  • July 14, 2025

That’s great, ​@stankovski! Keep us posted on how it goes with sequential execution, fingers crossed it’ll sort it 🤞

S
  • stankovskiBeginner
  • Author
  • Beginner
  • 5 replies
  • July 26, 2025

OK, I can confirm that switching to sequential execution has resolved the issue. Thank you all for your help!

SamB
Community Manager
Forum|alt.badge.img+11
  • SamBCommunity Manager
  • Community Manager
  • 9736 replies
  • July 28, 2025

YAY!!! 🎉🎉🎉 You’re welcome, ​@stankovski! I’m so pleased switching to sequential execution did the trick. 😊

Do reach back out if you need help with anything else at all. Until then, happy Zapping! 😁⚡

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