Hi.
Begin from these steps:
1. Open the cli (birdc), then run the diagnostic commands. Also, you can run the commands in the shell cli (without interactive mode and autocompletion)
2. Run the command "show protocols all". It lists detailed information about configured protocols (include pseudoprotocols like 'device') - check the states of protocols - obviously, your protocol should be in the UP state.
3. There're a tons of reasons of what can happens wrong. If you don't see established BGP session, run the tcpdump and check the traffic.
These step are basic troubleshooting tactics. Ask more questions and provide more information.