Why are commands not entered in PUTTY when connecting via RDP to a remote desktop (Serial port \ COM)?

Question

Command line

On the host machine, a Robotics V. Everything modem is connected to the serial port. Created a virtual machine on VMware on Win10x64. I connect to the VM via RDP with port forwarding. I open PUTTY, I connect to the port. The console shows the response from the modem (there is a functional button on the modem), but my commands that I enter are not displayed and are not sent (there is no response from the modem either).
Moreover, when the answer comes from the modem, it is clear that my commands are in the buffer.
For Win7 and Win8.1 there is no such problem.