No crank, no start

[Armanti]

So I recently bought a Lexus ls400 1990. I’ve had it for over a month now but the 3rd week of owning it, it wouldn’t turn on. When I try to turn it on all I hear is like a single click from under the glovebox or near the glovebox. There’s no click coming from the starter unless the single click I hear coming from the glove box is the starter trying to start. Check engine light is on & the battery is fine got it tested. Anyone have an idea of what’s wrong with it before I take it to a mechanic?