One of our Moen shower faucets started leaking after 3 years with minimal use which means the cartridge needs to be replaced.
Moen customer care was hit-and-miss. Digital/web-based support offered to send me one as a goodwill gesture as I was not the original owner / installer of the shower faucet set and I did not have the receipt, so they offered to send it to me for free but $15.00 shipping.
I called their toll-free number and was routed to their US-based care centre who offered to send me a new cartridge at zero cost.
If anyone is looking to purchase Moen products, I have a discount code that is good for anywhere between 20 to 75% off on their website. The discount code is good for 6 days from this post. Please PM me if you can benefit from the discount code and I will share.
Edit: I just browsed the portal. Some of their prices, depending on the product, even after discount, are not jaw dropping, so keep your expectations low.