recover forwarded email to gmail

[RAP Rally]

Dear all,

I wanted to forward roundcube email to gmail. So via gmail account i found Accounts and imports. Though, I forgot to select the button for archiving email in roundcube webmail.
So now i have 900 new emails in gmail and no copies left in roundcube. How can i restore that?

Please advise.

Thank you very much.

With kind regards
Tom