According to national technical regulations QCVN 41:2024/BGTVT on Road Signs issued under Circular 51/2024/TT-BGTVT (effective from January 1, 2025), the regulations on signs prohibiting parking are as follows:

According to the above image, license plate P131a is valid and prohibits motor vehicles from parking on the side of the road with a license plate.
License plate P131b is valid and prohibits motor vehicles from parking on the side of the road with license plates on rare days.
License plate P131c prohibits parking on even days.
If the driver parked on the wrong day, the driver will be punished for parking in a place with a "no parking" sign. The fine is from VND 800,000 to VND 1,000,000 according to Point e, Clause 3, Article 6 of Decree 168/2024/ND-CP:
People should note that Clause 4, Article 18 of the Law on Road Traffic Order and Safety (effective from January 1, 2025), drivers of vehicles participating in road traffic are not allowed to stop or park at the following locations:
One-way left side of the road.
On a curved road or near the end of a slope where visibility is obstructed.
On the bridge, except in cases where traffic organization allows.
Under the overpass, except for places where parking is allowed.
In the same direction as another vehicle that was stopping and parking on the road.
From cars parked in the wrong direction less than 20 meters on a narrow street, less than 40 meters on the road, there is a lane for motor vehicles in one direction.
On the pedestrian section of the road.
The intersection and within 05 meters from the intersection.
pick-up and drop-off points.
In front of the gate and within 05 meters on both sides of the gate of the agency or organization's headquarters, there are roads for vehicles to enter and exit.
In places where the road is only wide enough for one lane for motor vehicles.
Within the safe railway area.
Hiding road signs and traffic lights.
On the road reserved for buses, on the mouth of drainage culverts, the mouth of phone lines, high-voltage power lines, and a place reserved for fire trucks to collect water; on the road, sidewalks in violation of the law.
Note, in case of technical problems or other force majeure that force parking, when parking a vehicle occupying a part of the road or in a place where parking is not allowed, there must be an emergency signal with lights or a warning sign on the back of the vehicle so that drivers of other road vehicles know.