Running out of IP addresses

Hey Guys,

So the company I am working for is running out of IP addresses. We have a 10.0.2.x network with a /24 subnet mask ( Don't asked me why they did this because I just started at the company a couple of months ago.) My question is how should I tackle this problem. Can I add another range into our network? eg. 10.0.3.x for PC, 10.0.4.0 for phones, etc... with the same /24 subnet mask. Or increase my subnet mask to /22 so I would have a lot more addresses. Which solution is better?

Thanks