ISO 8601 date string format

Hello, I’m having a problem with the date format required when booking an appointment through Cal.com api Create a booking - Cal.com Docs

I have the output date in ISO 8601 date string format and I keep getting an error.

What could be happening?


Based on the example in the docs you’ve linked, it seems they don’t want milliseconds:

However, in your screenshot, you’ve included the milliseconds. Have you tried without those to see if it works?

First I tried without milliseconds as it says it should be done, and then I tried with milliseconds, anyway I have tried again.

It is true that there is one thing that I don’t understand: when I set the JSON format to ‘Expression’ instead of ‘Fixed’ I get different errors.

As for the error of the ‘expression’ format, I don’t understand it either because in the configuration of the event that I want to schedule there is no mandatory field not filled in, the requested by the event in Cal I am providing it in the http node. It seems that the error is because a field is missing.

Maybe it has to do with the ‘Response’ option of the http node.




I was able to create an event using this:

Could you share the output of your code node that you’re using in the JSON body so I can create an example for you?

How have you configured the event in Cal?, now I have tried to put the date of your example and I get other things wrong.

As I said before, there are no fields to be filled in the booking form.

and as for the email I don’t know why it gives me error if it is well written



I just created a new event type and used the default settings. I haven’t changed anything in terms of event settings.

I tried it with a code node and still get correct results:

I have created another event, and I have changed a little the json body and now the error I have is the following, I don’t understand why either, I guess it has something to do with Cal and not with n8n.



You can go to cal.com’s API page and enter the same data that n8n is sending. If it works there but not on n8n, then it might have something to do with n8n. If it doesn’t work even there, there’s something wrong with the data that you’re sending or with Cal.com.

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