You’re working with someone that responds rigorously to your emails, but the content (and the pattern) is always the same – you ask for A and the response is that A is being worked on and it will be available tomorrow, due to X, Y, Z.

Then tomorrow never comes.

What do you do?

My technique has been to log these promises and bump on the promised dates. After a while, person in question gets it.

Do you have any better solutions?