What's wrong my iguana....

I have an iguana who is untamed. When I feed it, it allows me to pet it, hand feed it, and even put its hand on my fingers (it's only around 1ft and I do not know the sex which is why I keep referring to an it). Anytime I try and get near the iguana when it is not eating, it gets intimidated and whips me with its tail. I cannot even put my hand near it through the cage without it freaking out on me. I have a basking light, a UVB light, the cage is 4x2.5x2.5 feet, and it has climbing material. The cage is on average 80ºF and the basking spot is around 90ºF. I have followed many taming guides online, but none seem to work whatsoever. At one time, the iguana did climb my arm, and I was able to hold it. I was getting very excited and happy. But I maintained my cool. Well the iguana jumped off me, and ran to the other side of the room. Any time I tried picking it up, it freaked out. But if I already have it held at the time, it was ok. But I want it to be ok just to get near it without it whipping me, as this could hurt if it is bigger. I am on the verge of replacing it for a tamed iguana...What should I do?