it looks like the d-channel is down. What kind of indication the local PTT receive? How is your E1 port configured? (multi-framing, signalling and etc.)?
it could be configuration mismatch, and it also possible that there is some kind of problem with the transmission – try to change an E1 port on the transmission equipment or to check the configuration on the transmission equipment regarding TS16 (some transmission equipment can manage TS16).