Uv ink crack

Hello somebody can help me why my uv ink crack on phone case i use this ink before without problem but now i have some cases and the design was crack on case

 

The ink is probably not well cured for a large layer of paint. Try adjusting the setting to use fewer colors. Or maybe degreasing the cover will help.

 

Dear Sir
I guess that your ink is too much cured.
Try to reduce the UV percentage, or increase your machine speed.
Good luck

 

Well you have got 2 good answers there.... 1 says ink not cured enough & 1 says ink is over cured.... so another words no one really knows.

Are you putting a varnish over the ink ?

Are you leaving enough time to allow the ink to cure before creasing it ?

 

It may also be that the ink has expired. UV inks have a 6 month expiration date once opened. Unopened I think that the conservation in an opaque bottle is 2 years.