Hard to tell without seeing the account, but a few things come to mind.
How's your conversion tracking set up? If you're just assuming no one's calling or booking, the tracking itself might be the issue rather than the actual results. Worth a sanity check there.
If tracking's fine, then yeah it's probably a mix of both.
On the ad side - what keywords are you running? Broad and phrase match can pull in a lot of window shoppers searching for "how to detail a car yourself" or "best car detailing products". Those will never book. Pull your search term report and see what's actually triggering your ads. Add negatives for anything that's not someone looking to pay for a service.
On the website side, a few quick checks:
- Is your phone number visible right away, and clickable on mobile?
- Do you have a clear CTA above the fold? "Book now" or "Get a quote" works.
- How does it look on a phone? Most local service searches happen on mobile.
Also, are you using call tracking? For a detailing business, most conversions are probably phone calls, not form fills. Without call tracking you could be getting leads and not even knowing.
What's your rough daily budget and how many clicks have you had so far?
Honestly at this point it might be worth paying for a few hours with someone who knows what they're doing rather than just burning more cash. Chances are it's something straightforward (and no, it's never actually straightforward - I've managed campaigns for years and still find blind spots in a few hours of YouTube tutorials).