Net::SMTPSyntaxError in HackathonMailer#submission

[appsignal]

Message

  501 Invalid RCPT TO address provided

Backtrace (last 10 lines)

lib/net/smtp.rb:1076 check_response
lib/net/smtp.rb:1044 getok
lib/net/smtp.rb:972 rcptto
lib/net/smtp.rb:954 block in rcptto_list
lib/net/smtp.rb:952 each
lib/net/smtp.rb:952 rcptto_list
lib/net/smtp.rb:768 send_message
lib/mail/network/delivery_methods/smtp_connection.rb:53 deliver!
lib/mail/network/delivery_methods/smtp.rb:101 block in deliver!
lib/net/smtp.rb:612 start

View on AppSignal: https://appsignal.com/hack-club/sites/64dc848fd2a5e4d7b35c5ca2/exceptions/incidents/65