I am neewbie to BGP. I have created neighborship

R1 <-> R3 E-BGP Neighborship

R3 <-> R4 I-BGP Neighborship

R4 <-> R6 E-BGP Neighborship

I have advertised loopback network 1.1.1.0/24 on R1 and 6.6.6.0/24 on R6.However R1 is not learning 6.6.6.0/24 network and R6 is not learning 1.1.1.0/24 network. Please let me know what wrong I am doing.

Attached is my network snap

1: https://i.sstatic.net/WxBEuFCw.png`enter code here`