Radar detector fuse install issue

Hello,
I am a first time poster long time reader. I am trying to run a few mods on the truck, but
I am stumped and I gave up for awhile until now for the radar detector. I decided to tackle it again since I have to run wires anyways. I am hoping someone can help me out I am trying to hardwire a Uniden R3 radar detector to my fuse using a fuse tape. I ran all the wires and got stuck at the fuse wiring part. I tracked down the fuse for turning ignition on to give power to the accessories. I used the piggy back fuse tape and crimped it to the red wire from the radar detector and ran it to the fuse box and the black to ground. I powered it on the vehicle but the radar detector does not turn on. I though maybe the ground was an issue so I used a car power pack booster to ground it but nothing happen. Than I place the black wire back to the ground on the car again and pulled the piggy fuse and put it on a car booster battery pack and it powers on. So it has something to do with the fuse. Any suggestions on what fuse I should piggy back off of or idea of what mistake I am doing? The ones that I have already been taken for other accessories are acc (7.5 A), dr lck (20A), and the one between Ig1 No. 2 (10 A) and IG1 (10A).