national insurance question

[movingtables]

So the new rate in July2022 will fall inline with the tax threshold
of £12,570.
I am semi retired (47) and only work 3 days (20 hours @ £10ph) so earn less than the new threshold.
but i have about 7 years left of national insurance contributions left
to receive full state pension for when i fully retire.
If i am not paying any national insurance from July that means i am not paying any more stamp, is that correct ?

If so will playing voluntary contributions of £3.05 (class 2) a week rectify this?

thanks.