At-command with Sierra MC7455 on RB912UAG-5HPnD worked on 7.1-rc1 but not on 7.1-rc2

RouterOS RouterOS beta
1

In ver in 7.1-rc1 AT-command sims to be working

[admin@MikroTik] > /interface lte at-chat lte1 input="AT"
  output: OK

But the same command is stuck when running on ver 7.1-rc2

2

with R11e-LTE6 works

/interface lte at-chat lte1 input="ATI"
  output: MikroTik
OK

Beter when you write directly to support http://mikrotik.com/support