Ensure you have given mic access if you are using a Mac.
https://support.presonus.com/hc/en-us/articles/360018329172-No-Audio-Input-on-Apple-OS-X-10-14-Mojave
If its a PC or if the issue remains then please log a support ticket.
https://support.presonus.com/hc/en-us/articles/210050813-How-to-create-a-new-Support-Request-