Keep getting accused of being "the bad guy" when I point out gaps in processes

I run a Supply Chain department for a food manufacturing facility. Naturally, I coordinate with a lot of vendors and customers.

I fully expect issues to come up from time to time, but I also expect to work as a team to mitigate specific issues in any way possible for the future. It's not unusual for our customers to ask my company to find root causes and write corrective action reports when issues happen.

That being said, there have been some times recently where I was told I was being unreasonable when I point out a specific issue keeps reoccurring.

I had it happen with an ingredient supplier- I pointed out there was a breakdown in communication recently, but then I pointed to the fact the same issue happened 3 months ago, then 6 months ago, a year ago, two years ago, etc. I shared all of the evidence and I was initially told "we need to focus on the current issue". Naturally, as it is well within my right, I pushed back and specifically identified where the gap is and why the root cause of the current issue and the previous issues are actually the same. Eventually they acknowledged there was a gap and they agreed to address it.

There's another ongoing issue with a logistics company I deal with that makes mistakes on deliveries. It's a recurring issue and the root cause is always the same- product was labeled incorrectly on their end and it was shipped incorrectly. Every time I point this out and/or offer to help to mitigate the issue in any way, I'm always told "don't worry about it, we will fix the issue on our end, there's nothing you need to do". Then a month or two passes and the same exact issue comes up. Just recently I sent a note to the leadership team stating specifically about what should be done, how we can't continue making the same mistake, etc. and I was accused of jumping to conclusions. The evidence I shared clearly show the root cause of the mistake is exactly the same....

I have more examples but basically what I want to get at is I want to try to find a way to work together with my partners when these things happen. If any of you have experienced something similar and have success stories to share I'd love to hear them