that is odd that it is always sharp. How sharp are you?
What make/model of clarinet is it?
Some clarinets are made (per the manufacturers specifications) as a 442 instead (or also) of the 440.
Also mpc manufacturers offer options such as tuning to 440 or 442.
So, theoretically, one answer could be that you are using a 442 clarinet and trying to tune it to 440
but more information is needed - what is your setup - reed, mpc, clarinet ?
What make/model of clarinet is it?
Some clarinets are made (per the manufacturers specifications) as a 442 instead (or also) of the 440.
Also mpc manufacturers offer options such as tuning to 440 or 442.
So, theoretically, one answer could be that you are using a 442 clarinet and trying to tune it to 440
but more information is needed - what is your setup - reed, mpc, clarinet ?