This is the summary of the whole problem. The Covid pandemic made a lot of people (owners, investors) fear a recession, so they started closing all kinds of industries, incl. paper mills. But there was no recession, and in fact the economy (mostly) kept going full speed ahead. So, huge feedstock shortages happened. In addition, the container shipping is all messed up, because (1) companies don't want to haul empty containers, (2) some boat blocked the Suez for a week and (3) China closes entire port cities if there are a few cases of Covid. So, lack of feedstock and lack of transportation. And on top of that there is a massive lack of employees in many countries. None of that helps the supply chains. I expect the world's economy to be very volatile for a while to come. But paper shortages for printing are nothing compared to the grain shortages that we will see soon.
I'm curious what the "production issues" are. Shortage of paper? Ink? Shortage of printing facilities? People? Containers?
Hope our DM doesn't get inspired by all this. "Sorry, your wizard cannot copy that spell. While there's plenty of ink, the next shipment of paper and parchment only comes in 6 months from now, as there is no papyrus to make it, no crates to pack it in, no boats to ship it and no people to sell it to you. Maybe it's time for a side quest, where you set up your own logistics company in a tight labor market?".