Transition from /p/ to /v/

I would like to know how /v/ is pronounced when it comes after /p/. For example: upvote

My lips come close to each other in order to produce /p/ and after the puff of air from my mouth, it becomes harder to produce /v/.

Could you please tell me how you produce /v/ after /p/?

Thank you.

The problem is the "puff of air" on /p/. You are effectively pronouncing the up- of upvote as a separate word — and, indeed, clearly enunciating it as a separate word.

When /p/ is followed by another consonant, such as upvote, update and maybe even upholster, the /p/ is not actually a plosive; it's a stop. That is, there is no "puff of air". Even if you have to reorganise and reposition parts of the mouth between /p/ and the following consonant, don't release air.

Try it slowly: say up but stop when the lips come together; hold your breath and then say vote (or date, or whatever). With practice you can run that together. But even without speaking at speed, you are not "finishing" the /p/ sound as a distinct plosive, so it will be obvious that up- is connected to -vote. (It will sound like you have a stammer, so making the stop as short as possible is a good thing.)