PIP while serving Notice Period

Hi All,

Need to understand putting into PIP matters while serving the Notice period.

I was a top performer but after submitting my resignation obviously I slowed down the work and started delaying the work and My manager put me into PIP.

I just wanted to know whether it really matters PIP while serving NP, Will there be any consequences that might arrive in the future or situation and any issues will happen for the experience letter, How to deal with this situation.