‘It’s a vicious circle’ or ‘It’s a vicious cycle’ ?

Depends on if you’re talking about life or an ouroboros

It’s a vicious circle

I have never heard anyone say this.

Cycle.

Google is dumb.

My girl is an irrational a-hole for 5 days every month without fail. You could say it's a vicious circle of vicious cycles.

The original expression was “vicious circle,” used in the sense of a circular argument.

Logicians in the early 17th century used the term “vicious” (from the Latin vitiosus, meaning faulty or defective) to refer to a flawed syllogism.

Here’s an OED citation from 1697: “If from true premisses follows what is false, it is a sign that the form of the syllogism is vitious.”

By extension, the phrase “vicious circle” was used in the 1700s for an argument that circles back on itself because its premise is flawed (usually the premise is used to justify the conclusion, which in turn is used to justify the premise).