With conditional emails are not sent

Since a few weeks ago I have problems with sending forms to my email when before everything was working correctly.

I have a form that shows conditionals according to the user choice.

Once the choice is made, the user has to fill in the fields and attach a pdf or jpg file.

I receive in my email the form data plus the attachment.

Now, since a week ago, when I click on Send, the form keeps trying to send and does nothing.

If I deactivate Conditional Field, the form is sent correctly.

Any help?

Thanks

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