Thank you for your Grohe faucet purchase. I am sorry to hear you have had issues with your faucet. We do offer a limited lifetime Warranty against manufactures defects. I am sorry to hear you had trouble with the customer car team when you called in. I will pass your comments along to the customer care manager. We try to get the correct parts to fix your problem the first time but sometimes human error intervenes. The agents on the phone will trouble shoot the problem with you to make sure the plumber is giving you correct info. You can follow our warranty link and fill out the form for replacement parts https://www.grohe.us/en_us/our-service/warranty/ . Please feel free to contact us in the future if you have any other inquiries.
We can be contacted at us-customerservice@grohe.com