When trying to create a Zap and connect it to Customer.io, I got the following error:
We hit an error adding your new account authentication failed: The app returned "Page Not Found | Customer.io".
It was working fine just a week ago with the same setup.
I also double-checked that I’m using the correct Site ID and API Key from the Track API Keys section in Customer.io.
Nothing has changed on my side, so I’m not sure what’s going wrong.
Is anyone else seeing this issue recently?
Hi
Welcome to the Community.
If you're having trouble connecting your Customer.io account to Zapier, it may be due to a few common issues. First, re-enter your Site ID and API Key; even a small error can cause problems. Check Customer.io's status page to see if any current outages or API issues could affect the connection. You can also test your API key directly by making a simple API request—any errors you receive might point to a problem with your key or account. Additionally, recreating the Zap from scratch can sometimes resolve hidden issues. If none of these steps work, contacting Zapier Support for more detailed troubleshooting assistance is best.
Please know that we're here to help and will do our best to resolve this for you as quickly as possible.
Hi there 
Just came across this and couldn’t see any tickets from you with our Support team. Did the issue resolve itself or did you manage to fix it?
Want to make sure everything is up and running again so please keep us posted on how you’re getting on! 
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