Dishonest business, mechanic caused more issues than fixed

They came to fix my wife's car, which had no electrical issues whatsoever. Simple replacement of the fuel pump and thermostat and ever since the lights flicker and the battery drains. They claim it was the battery which we then replaced and now they say they did an inspection and as such we need to pay them to come figure out what their mechanic broke.

Dishonest business practices and will just milk you for more money over and over