Sidechain send not appearing until restarting cubase

This is on windows 10, cubase artist 9 however was experiencing the same issue on cubase artist 8.5

Whenever I create a sidechain compressor on a channel, I cannot send an input to that channel until after I restart cubase as the side chain send doesn’t show up in the list.

After restarting, the sidechain will usually be listed in the list of sends.