I know I am late to this party, but thank you for your help.
I know of the approved URLs that can be placed in gigs as the following list shows:
https://www.fiverr.com/support/articles/360011421218
ammyy.com
blogspot.com
flickr.com
mixcloud.com
reverbnation.com
soundcloud.com
spotify.com
teamviewer.com
tumblr.com
vimeo.com
wetransfer.com
wikipedia.org
youtube.com
But I am unable to create links in my Fiverr gig descriptions such as to YouTube or my other Fiverr gigs. Is their a certain script I can use to create links or do I have to be at a certain level to create links in my Fiverr gig descriptions?