Struggling with finding the right medication for my anxiety and depression

I’ve been on various medications before with my family doctor to treat my anxiety/depression(Mostly SSRI’s), but all of them either did nothing or made it worse. I’ve been seeing a psychiatrist for the past year-ish and a couple medications(mirtazapine and venlafaxine) started as having an affect but gradually stopped a week or more before my checkin appointment for the meds, even though I’d been taking it consistently. And the medications didn’t have any affect on my anxiety or depression more my appetite and sleep schedule. Any ideas on why that might be? Suggestions on medications or tests I should take to help us get a better idea of what I should be taking?