Error: Vswitch already exists after first run

[adeleneleda]

Hi! I tried running ./bin/trema run lib/hello_trema.rb -c trema.conf and it worked fine the first time I tried it. But after killing the process with kill -9 and restarting it again through the run command, the following error occurs:

RuntimeError: a Vswitch #<Vswitch name: "0xabc", dpid: 0xabc, openflow_version: 1.0, tcp_port: 6653> already exists

I have tried restarting my Ubuntu virtual machine as well but the same error persists.