help, this is my 5th round here and bumped into an issue i have never had. 14 cuttings all from the same mother and only 7 are doing well. all clones were rooted in rockwool 2 insc cubes and were looking ok. roots were just starting to come through the bottom o the cube so they were transplanted into the netpots with clay pellets. 7 of them are going just fine and the roots are looking healthy where as the other 7 are doing absolutely nothing not even growing into the pots yet. its not day 8 and still nothing anyone have any ideas what it is and what can fix it.

i am running the house of garden nutes A+B and root excel right now