Call not connecting

I have created two accounts in sip.conf file and registered with the dialer
Let the first account is A and the second one is B
1,When I dial extension for B, I am getting error 488 not acceptable here
2,When B dials the extension for A, I get the incoming call and when I answer the call it gets disconnected automatically

For (2) kindly see the logs below
== Using SIP RTP CoS mark 5
– Executing [8001@users:1] Dial(“SIP/abdul-00000004”, “SIP/arun,50”) in new stack
== Using SIP RTP CoS mark 5
– Called SIP/arun
– SIP/arun-00000005 is ringing
[Apr 30 20:48:26] ERROR[27387][C-00000042]: netsock2.c:305 ast_sockaddr_resolve: getaddrinfo(“0122ec0cI4”, “(null)”, …): Temporary failure in name resolution
[Apr 30 20:48:26] WARNING[27387][C-00000042]: chan_sip.c:10914 process_sdp_c: Unable to lookup RTP Audio host in c= line, ‘IN IP4 0122ec0cI4’
[Apr 30 20:48:26] WARNING[27387][C-00000042]: chan_sip.c:10475 process_sdp: Insufficient information in SDP (c=)…
== Everyone is busy/congested at this time (1:0/0/1)
– Auto fallthrough, channel ‘SIP/abdul-00000004’ status is ‘CHANUNAVAIL’

Please help me to solve this as I am very new to asterisk

Isn’t this the one I already answered?

getaddrinfo(“0122ec0cI4”, “(null)”, …): Temporary failure in name resolution

0122ec0cl4 is neither in your sip.conf nor a domain name that your name resolver can cope with.

I am sorry I can’t understand, I don’t know what is 0122ec0cl4 , I have dialled 8002 only.
Can you please be more specific

Looking more closely, it is actually the far side that is sending a bogus address.

The peer has told you that it wants audio sending to 0122ec0cI4. The only possible interpretation for that is that it is a domain name, but you domain name server is saying it doesn’t know what it means at the moment, but it can’t be sure that it won’t know later.

The same user and password trying from different computer and network its working fine. The issue is only when I am using it from my home, using my home computer and network. Please let me know how can I Isolate the issue to fix this. Is this because of my internet issue, its very slow in my home

The calling system is misconfigured, or a router is making a mess of the request.