I am in USA. I work for a software company which has many offices in USA & the rest of the world. Our company has very flexible work policies in general. Very few teams work from office, and usually not for the whole week. As an aside, there is a high turnover in our company and we have far more ex-employees in the past few years than new ones.
I was recently moved to a team which is in USA, but is in a different time zone than mine. I even did a business trip and worked with the new team in their office for a few days. The application which we are working on is quite mature and we are not adding too many new features to it. So, it seems that there is not too much work.
I can be 100% remote, but I work a few days from the office in my location. Sometimes, my teammates work from home, but they do not send an email or calendar invite to notify us. On such days, I sometimes have to wait for 1 hour or more to get an acknowledgement to my chat messages. My manager also appears "away" on our chat tool for a long time sometimes. I don't want to assume the worst, but it concerns me when I don't get responses for a long time and it hinders my work.
I would like to bring this to my manager's attention without calling out any teammates. But, I am afraid to do so because it will be obvious which particular teammate is responsible for my concern. That person has most of the knowledge about the application and I would not be able to get started without their help. So, I don't want to risk losing their help by antagonizing them.
How do I make my remote teammates accountable without causing any problems ?