no fermentation

Hello,
i recently brewed a La Trappe Clone, i did a 10 gallon batch and split it into two separate carboys.
one carboy i put in wyeast smack packs ( i double pitched the carboys due to lack of time for making a starter) the second i pitched with white labs wlp550. the wyeast took off fermenting right away, the white labs however, didn’t. i left it for a little to see if its just a slow fermentation but it wasn’t, after a while i though maybe there wasn’t enough cells so i pitched a wyeast smack pack into it as well. it still has not started fermentation. and its been quite some time.
any help ???
Thanks

I guess there’s a couple of things you can check;

Fermentation that starts right away isn’t necessarily the best thing for your beer. The lag phase can be up to 15 hours. A proper lag phase allows yeast to absorb oxygen & build sterols etc. You didn’t say how much time has elapsed since pitching?

How does the gravity currently compare to your OG?