Faucet mixer no hot water

Hi

I fitted a faucet mixer yesterday similar to the one pictured. Cold water works fine, pressure fine. However they get no hot water, and the pressure out of the hot water tap seems half of what it should be. They have this installed next to the toilet as a bidet type gadet. The pipes to this are fed of the basin hot and cold. However the pressure on the basin hot seems to be fine. I installed brand new pipes and know they are definately not blocked.

I've never opened up a faucet tap before so not sure what could be the cause.

Any ideas?

Much apreciated

I am no plumber, but..

I had this before after doing some work indoors and some jet blue was stuck in the filter in the actual tap itself.

also check your iso vavle you never no you may left it off