ios - Webservice class instance does not persist, unrecognized selecter sent to instance -

i've been looking @ issue having ios app , it's webservice class. seems class gets initialized , assigned instance, when try trigger class starting timer button, seems instance has been removed memory. how initialize (and try instance from) class.

+ (reflexionsmetawebservice *)getinstance {     static reflexionsmetawebservice *instance;     static dispatch_once_t oncetoken;      dispatch_once(&oncetoken, ^{         instance = [[reflexionsmetawebservice alloc] init];     });     return instance; } 

i've determined button that's calling class working intended cleaning references mentioned in other topics on forum. there maybe cleaner way initialize , maintain our webservice class instance?. hope above information enough.

i think assigning instance object gets released memory. don't think have problem webservice class, of it. put log message check class reference , assigned reference before timer kicks in , see problem is.