Great interface, awful customer service

Gusto is more user-friendly than other payroll software I've used. The interface is well done. However, I'm beyond disappointed with their customer service. If you need to ask a question (ex: why aren't federal taxes being deducted?), you're out of luck [in my experience]. I submitted this question along with a letter from the IRS to Gusto 2 months ago at this point and have yet to get a response. When I call, I wait on hold for [what feels like an] eternity before connecting with someone who can't help me. They'll say their tax team is very busy and will get back to me by X date. But no one has ever gotten back to me. [I feel like] my questions are just sent into the ether. I think new users should just know [from my experience] that they're not going to be able to speak with a human at Gusto who can answer setup questions. [I would] budget a payroll/tax advisor consulting fee into your costs when you're signing up. And [in my opinion] don't bother calling them because it's just upsetting.