Hi Khalid,
We’re here to help! If you haven’t called us already, please do. This model can flow up to a maximum of 1.2 GPM. We can troubleshoot what’s happening with your faucet and send you any necessary parts to correct it. This faucet is equipped with screens in the inlet adaptors to prevent debris from flowing into your faucet. The maintenance guide has cleaning instructions to clear any loose debris that may have gotten caught up in the screens that could be restricting the flow. Below is a link to these steps; please refer to the 3rd page, then step “Adaptor Cleaning.” If cleaning the adaptor screens doesn’t help, we’ll need to send you the cartridge replacement. Please call us at 1-800-732-8238 for further assistance with your faucet.
https://pfisterstorage.blob.core.windows.net/documents/47511-0500%20web.pdf
Thank you,
Pfister