send e-mails from arduino wifi mkr1010


My question is regarding sending e-mails from arduino wifi mkr1010. (without using IFTTT)
I tried with the installed libraries and none worked. (They are supposed to connect to my gmail account with user, password and port 587 to smpt server and send a mail)
My arduino recieves this message:
Must issue a STARTTLS command first.

Can anyone give me a hint what should I change or add in the library? I have some experience programming, but not in smpt and I have no clue where should i look at.

thank you

As I did not find a better solution I started using IFTTT Webhooks.
I uploaded my current project here: