You can not change the weather...

Nobody needs to explain to a sailor that it is useless to challenge the wind. Sailors just know they need to adjust the sails to the wind to reach their destiny. 

Although it might be difficult to link this to you as a manager, it is actually a very logical approach to consider at times.

That are the moments you are fighting a battle you cannot win.

How did you get into such a battle in the first place?

Mostly, because you forgot to listen to this little voice in the back of your head that already knows long before that you are going to waste a lot of energy.

Seeking for examples? Getting approval for a salary raise for one of your top guys whilst line management has issued a salary freeze. Or getting one of your top-guys to an event abroad while there is a travel ban.

In such cases I would strongly suggest to rethink your tactics. Instead, like sailors take the weather as a given, accept the circumstances as a given and focus on objectives you can reach. In the given examples think of alternative motivators, such as added responsibility, ownership creating more professional visibility or in the case of the travel ban propose local event options in the field of interest or added professional personal training.

It might need some thinking outside-the-box to seek an option that serves your goal, but you know upfront this is not energy lost. And while doing so, and fits the purpose, it does not hurt to challenge the boundaries of your authority. These may reach further than you think!