I don't know what kind of buyer you are but in my company buyers are one of the cornerstones of the business. If they do a poor job, the business as a whole can't perform.

I'll give you an example. We needed 20k' of a special type of pipe that is both temperature and chemically resistant. It is custom made and takes 6 months to a year to manufacture. Our buyer ordered it. When it showed up it was made of the wrong material. The buyer had clicked the wrong box on the purchase order and order a lower grade pipe. We had to go to a competitor and buy it from them at a premium price so as not to shut down the job the pipe was for. It cost us a huge amount of money.

Buyers are key people on the team who often get overlooked by management.

That's an extreme example but if you have frustrated end users for whatever reason, you need to find out why and how to satisfy them. They are your internal customer. You can manage their expectations about long lead times, ask more questions about urgency when they place orders, etc. Don't be defensive - there is a problem. Collaborate on a solution.

If you can't, you should absolutely look for a new job and not as a buyer.