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Power Platform Community / Forums / Power Automate / The datetime string mu...
Power Automate
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The datetime string must match ISO 8601 format.

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Posted on by 48

Hi,

 

I'm getting the following error on my flow when sending an email:

 

Unable to process template language expressions in action 'Send_an_email_(V2)' inputs at line '0' and column '0': 'In function 'formatDateTime', the value provided for date time string '' was not valid. The datetime string must match ISO 8601 format.'.

 

It started today, but it has been working so I'm a bit confused.

 

CopeStarr_1-1662983118474.png

 

CopeStarr_2-1662983136993.png

 

CopeStarr_3-1662983176769.png

formatDateTime(variables('DateofCall'),'dd-MM-yyyy')
 
There is another date variable in the flow with same issue - DateOfFollowUp
 
It was all working on Friday, which is why I'm scratching my head - successful flow below and email was received with correct date format
CopeStarr_4-1662983272116.png

 

Thanks for any help offered.

Darren.

 

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  • David- Profile Picture
    1,254 on at

    Please show what is being returned in the Set variable DateofCall action. I suspect that it is not setting the date as 'yyyy-MM-dd' which is the ISO 8601 format that is expected in the expression in your Send e-mail action. If you are already formatting this date how you need it in the Set variable action, you can just use the variable in your e-mail instead of doing a formatDateTime expression on the variable.

     

  • CopeStarr Profile Picture
    48 on at

    Hi David,

    Thanks for the reply - appreciate it.

     

    I think this is what you asked for:

     

    CopeStarr_0-1662984496190.png

     

    Regards your 2nd statement about not using the expression, I'm sure I've probably made this long-winded in my approach. I haven't set any exact data parameters anywhere else, which is why I assumed I had to do it via an expression? I'm learning on the job so not an expert by any stretch 🙂

     

    Thanks.

  • David- Profile Picture
    1,254 on at

    That date format is correct, so it should have worked. I am stumped. 

  • CopeStarr Profile Picture
    48 on at

    Thanks for looking, David - The fact it was working and nothing has changed has me stumped too...

     

    Edit - Just gone back in and flows are now working again - I wonder if there is an issue at MS end - will have a look around...

     

    CopeStarr_0-1662988175811.png

     

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