It is the largest positive impact a single person can have on the environment. Kurzgesagt video with the analysis.
As a vegetarian for decades, it’s also cheaper, often healthier, and isn’t difficult at all once you find some new recipes you like. You also don’t need to switch all at once. Ease into it by cooking one vegetarian meal a week and then increase it as you find ones you like.
When I made the last payment on my student loan I got a similar letter. Something along the lines of “it appears you have made your last payment, but we still need to review the account to confirm. If you dont get another invoice from us then it’s all good.” I then got an invoice for about $1 which was the interest that gained on the account from the time I mailed the last cheque and the time they cashed it.
I’m going to assume this person sent in something that looked like a payment which triggered the “looks like you made your last payment” letter but then accounting realized the payment was phony and sent an invoice.