Panels resprayed

[Rad1o]

I know this is not a specialist car forum. But can anyone tell me what went wrong?

My daughter's Skoda has this horrible lacquer peel. So we / she decided to respray some parts of the car. The paint was sanded down often to bare metal. We used spray cans and started with primer / filler, then used the car's base coat and clear lacquer. The lacquer was Simmonez.
The panels were cleaned with alcohol wipe and a tack cloth before spraying.
The layers had time to cure.
It looked good, but after a few weeks cracks and small rings started to appear. The rings seemed to come after rain falls. The cracks just developed.
Very disappointed. At first I tried to polish it out and it worked for some small rings and minor cracks, but the cracks started to look likesome planetary rifts.

We also did the mirrors and I think it was a different clear lacquer. They are still o.k.

 

[Old Salt]

A reaction between the different paint layers e,g, manufacturer’s, bare metal primer/filler and Simoniz. You say the paint had time to cure but typically at least 24 hours is required between coats and that is in warm temperatures.

 

[Rad1o]

It was done last summer, so somewhat warm.
The cracking only appeared weeks down the line, not immediately.

Do you have any experience with paint work?
Can this cracking be fixed or is this ideally a paint off job?