I can't seem to keep my CO2 stable. The clamps on both ends of the tubing are tight but my CO2 levels keep dropping. I bought a new regulator so I don't think that is the issue.
Welcome to the BA site, @xu95. Your question would be seen by members who have answers and recommendations if it were posted in the Homebrewing forum or the Home Bar Forum. Or just go to one of those forums and do a search or read back a few pages or so. Hang around the site as long as you'd like, and enjoy your time while here.
Two ways to identify a leak - put a soapy water solution on all the connection points and look for bubbles, or briefly run the pressure up to around 45 and listen. You can also use the soapy solution with this test.
Over tightening of the regulator to the tank will deform stem washer and will cause leaking too. Or faulty regulator? Seen brand new regulators with bad diaphragms leak co2 out from the adjustment nut.
What, exactly, do you mean by that? The keg is not holding pressure (low pressure gauge)? The tank pressure (high pressure gauge) is dropping? The weight of the CO2 tank is dropping? The beer is going flat? These are all different problems with different solutions.