Do other hobbyists have a hard time getting responses from providers? For probably the fifth time in the last year I have written to a provider requesting an appointment and have gotten no answer. I've provided all the information and screening information requested, made no inappropriate remarks, provided several days notice... and nothing....

Are they active on social media?  Recent ter reviews?

Sometimes providers are busy and they might miss an email. Had that happen to me once or twice. Usually the best way to go about it is writing a (polite) follow-up email once, *maybe* twice, asking about your inquiry, and asking if there was anything else they needed from you. Shows that you're proactive and accommodating.

a couple of months ago i was trying to set up an appointment and come to find out the lady took a vacation.  

Regardless of reviews recent or not, social media helps.  
I think it’s uncool when ppl don’t reply either way.  
Maybe the email went to spam , after a few times I wouldn’t reach out anymore.

This happens way more to me now than it used to! Scheduling time for this is very tricky too, so I now have like 2 appointments a year if I'm lucky. It's not just you.

I think you need to move on and pick a provider who values your time and appreciates your business. I receive requests that fail to provide the vetting information I require and I still reply. I think it's unprofessional to not respond at all. What do I know I've only been here for over twenty years? 🥰

Depending on who you’re contacting, it’s possible that the several days’ notice might not be enough.

Sometimes availability isn't predictable and a few days is all there is. My point though is not that the lady isn't available in the timeframe I'd like. I completely get that. It's there is no response at all. I think that is bad business.