Mesut Ozil has quit the national soccer team (saying racism was the cause). Chancellor Angela Merkel and U.S. President Donald Trump have been sniping at each other. And to top it all off, German brewers say they’re about to run out of beer bottles.

Germans don’t drink their beer out of cans. (This is the country that’s home to the Reinheitsgebot, a beer purity law that has been enforced for over 500 years, after all.) Instead, they pay a deposit on bottles, which is refunded when they’re returned. But an ongoing heat wave throughout the country has discouraged people from bringing those bottles back in. And that’s causing problems.

Bottles are typically ordered a year in advance, too, so brewers, especially smaller ones, can’t just grab a new pallet or two. Instead, they’re appealing to customers to help them out.

“We need your help!” the Moritz Fiege brewery posted on Facebook. “Great weather + great beer = serious thirst. The catch: although we regularly buy new bottles, we’re running out. So before you go on your summer holiday, please be sure to return your Moritz Fiege empties. … Make your motto: first the empties, then the holiday!”

Beer has been problematic all over Europe this year, actually. One London wholesaler in June was forced to limit the amount of beer it sold to customers, due to an ongoing CO2 shortage in the country. That shortage is due to planned shutdowns of major ammonia plants along with maintenance shutdowns of several bio-ethanol plants throughout Europe, which also supply CO2. As of June, northern Europe only had five CO2 producers and only one is currently operating in the UK.