Hi about a month ago I replaced my bathroom sink taps last night was washing hands and pressure was good then all of a sudden dropped off to nothing but a slow flow with very little water

Water pressure in bathroom sink taps just stopped very low water flow

First thing remove the Aerator see the image below, try the water and see if it flows good, if it does clean Aerator install and check if your problem is fixed.

With Aerator removed and no good flow come back and we tell you What is the next step, Thanks.

John