Virgin Moible S3 root Question topic

i have and Samsung Galaxy S3 stock ROM and everything this i s my build "kot49h.l710vpucnj3" would this have anything to do with why i cant get root or i am missing something i have used Samsung S3 root toolkit i can flash a custom recovery but on initial boot it get removed by the system i also tried srsroot, tried cf auto root but that screw up my system perhaps i used the wrong one i am running viring moible 4.4.2 model SPH-L710

PS Thanks for your help