mx - Outgoing mail is not working. SMTP problem

MXPLAN1 hosting

MX

1 mx1.mail.ovh.net
5 mx2.mail.ovh.net,
100 mx3.mail.ovh.net

I transferred my DNS to freehosting.com Since then I have a problem with incoming mail. Outgoing mail works. Outgoing mail is not working. SMTP problem. What and where to improve?