Russia is the biggest exporter of fertilizer in the world. That may be causing problems.
China is a major exporter of phosphorus, and they ban exports from time to time.
Nitrogen fertilizer is made from natural gas, and the Iran war may be affecting supply.
I already bought several bags of triple 12 this winter to cover my needs for the year. Memards had it relatively cheap, so I loaded up before demand ramped up in the Spring. I like a diverse seed blend in my plots, so I always use triple 12, and that's what my trees and shrubs get. Keeps it simple and cheap.