Some users do not allow them to put the protection, I tried all kinds of thing and I have not found the problem, only happens with some users when it comes to putting the protection the block becomes a normal block, any solution?

O/ Hello.
50 shiney coppers says they are not sneak placing the block when that pstone requires sneak place?
And then they just said yes! Yes I sneak placed it!... When you asked?
There is a tiny chance these players also just got the plain block type for the pstone,
placed it and claimed it was a pstone when they placed it in an attempt to get a free one?
When you say "only some players" It sounds like you did things right but some of your players are perhaps blind to warnings and advice about pstone operation. They need very special care? :D
Or you missed a permission somewhere.

Make sure they have the right permissions.

In groups make sure you did not miss a whole group in the inheritance structure of your ranks.
They need a permission to use and to place. The claim stone's config should have something like

required-permission-use: PS-CSI
required-permission: PS-CSI
limits:

• 5
• 10
• 15
• 20
• 25
• 40

And your groups rank that is supposed to be able to use it should have
- preciousstones.benefit.*
- preciousstones.whitelist.*
- preciousstones.limit1
- PS-CSI
inheritance:
- groupname
Else they will have no permissions and every rank above them will.

In your starter group.

- preciousstones.benefit.*
- preciousstones.whitelist.*
- PS-CSI
- preciousstones.limit1

Higher groups..
- PS-CSII
- preciousstones.limit2
- PS-CSIII
- preciousstones.limit3
- PS-CSIV
- preciousstones.limit4

If it is a sneak placing thing?
Add 10.7.1 has new flag to prevent accidental not sneaking placement.
sneak-to-place: true
sneak-to-place-only: true