SMTP Test not working

Hello,

I tried test sending email as below:

SSH into console

go to project

$ php artisan tinker

$ Mail::send('errors.401', [], function ($message) { $message->to('your-email-address')->subject('this works!'); });

But it just displayed "null" in tinker.

I also tried the "Forgotten Password" and no email is sent.

I have MAIL_DRIVER=smtp

and using Sparkpost SMTP with working credentials.

Not sure what to do next. Thanks for your help.