Why do I keep forgetting details at work?

I think that it is normal to be confused now and again. From what I can tell from your post is that you are a conscientious employee that genuinely wants to do a good job, this is actually quite rare. Try to project confidence at all times even when you may make a mistake and try to use the radio only when you think it is absolutely needed. If you must use the radio, try and think of the best way to phrase the question so that it is quick and to the point.