How to create a bat file correctly? Sending an at request?

Question

Command line

Hello everyone)
I send AT requests to the usb modem via the command line.
The code looks like

copy con com8 (Enter)
AT^SYSCFG=2,2,3fffffff,0,1 (Enter)
^Z (Enter)

Everything works in manual mode. I tried to write this code in a bat file, but only the first line is executed.
Please help me create a bat file that would execute this code.

Answer 1

In general, I set up the transfer of parameters through PuTTY, thanks to everyone for the suggested options

Answer 2

ECHO AT^^SYSCFG=2,2,3fffffff,0,1>>COM8

Answer 3

first you need to understand what these commands do
write one line instead of your three
echo AT^SYSCFG=2,2,3fffffff,0,1 > com8