People who do remote work, what's your stance on making calls to get together to do things?

In my case, I have this tech lead boss now who's always available to start calls so I can share my screen and point at what problems I'm having, and I really appreciate that.

Other people at my job are really hard to get into contact with, they're never available when you need them, so if there's some conversation by the nature of which there needs to be a lot of back and forth exchange to get both parties on the same page, more than a day or more can be spent before work based on that conversation can be done.

I'm not talking about distribution of tasks, but rather "person with access to X, I need you to do Y". I invite them to have a call so we can explore how to do Y together, because neither of us know it too well, but they just do whatever, ask how it went, and it turns out wrong. In this particular case, I've got a marketing guy who has access to the company's business account in a social media platform. I need them to add me there as a developer, and make sure I and another developer have all privileges necessary to create and configure an application which will use the social media platform's APIs. Marketing guy just takes hours to respond and generally acts like we're not worth his time, but can't do the things we asked and dedicate the time to see with us if things are working before he sets out to do other work.

This isn't an isolated case, we've got other people who don't look at their messages and are just generally unavailable. Not sure if I have incorrect expectations. Everyone in the company works remote, but we're all in the same time zone.