So, if you've unlocked some Vampiric Powers with Potent Blood (or through challenges such as the Diablo 4 Accursed Touch power) , slotted up to five in your Sanguine Circle, and have the right Pacts on Diablo 4 Gold your armor, your Vampiric Powers should be activated and ready to go. However, if your Sanguine Circle says you that you've got inactive powers, that means you've not met the Pact cost.

The Diablo 4 Potent Vows objective is currently bugged | MMOEXP　　

If you're trying to do the Diablo 4 Potent Vow objective, you might have found that it's not progressing, despite wearing a piece of armor with five Pacts. The challenge is currently bugged for a seemingly small proportion of players. Conveniently, you don't have to complete every Diablo 4 seasonal challenge in a chapter to move onto the next one, so the Diablo 4 Potent Vows challenge can at least be safely skipped.

The Potent Vow challenge in Diablo 4 isn't working

Some players have found that the Diablo 4 Potent Vows objective, which requires you to equip a piece of Pact Armor with five filled Pact slots, is bugged and won't progress. To clarify, this challenge found in Chapter 3 of the Diablo 4 Season 2 Journey tasks you with equipping a piece of Pact Armor that says "Pacts Granted 5/5" on your character. You can also add a standalone Pact onto an armor piece that can take one to bump it up to five Pacts. This issue seems to be affecting only a small portion of Diablo 4 Gold for sale players and doesn't have a fix or workaround right now.