First month and already late rent | New house - old tenant

Hello BP community! It's my first post, but it won't be my last.

I just bought my first duplex property and against all advice decided to keep the old tenants... It is now 4 days after the first rent payment was due, where I asked for first and last month's rent. The boyfriend, who earns most of their income, has been "missing" for a few days, and the girlfriend is concerned he could be in trouble. We've just signed the 12-month lease and the only thing I've received is a security deposit. Would you have a conversation with the girlfriend about how she might be able to make ends meet or just send the Notice of Noncompliance and get them out on day 5? Is going through the eviction process really the best way, or is there another way I could remove and replace them that won't involve lawers and other financial and mental stress?

I'm looking forward to seeing your responses. Thanks!