Skill Unbound Avatar is useless

I took this skill test and it was useless. Here are 2 problems
1. It takes me about 3+ minutes to fully charge. I clear the location or kill the boss faster. As a result, this skill simply remains unused
2. The charge is reset every time I move from one location to another or return to the town. I would like to save it for the boss fight but it just disappears if I move from one location to another.

In the end, I just issued a refund for this skill