Tls call failure

i have configured two sip clients with tls/srtp.

i can only call from A->B
when calling fom B->A i get the following error.

[Aug 17 00:07:36] ERROR[8848]: tcptls.c:209 handle_tcptls_connection: Certificate did not verify: certificate signature failure

this was my referenece : wiki.asterisk.org/wiki/display/ … g+Tutorial