No such command 'sip reload' when using asterisk 18

Solution 1:

In Asterisk 18 the module chan_sip.so is set to noload in the modules.conf file.

If you want to autoload the module just comment the line by adding ";" in front of noload = chan_sip.so

[/etc/asterisk/modules.conf]

;
; Do not load chan_sip by default, it may conflict with res_pjsip.
;noload = chan_sip.so
;