Your temp is a little high for that yeast. Lager yeasts should, in general, be pitched and fermented at 60 or lower. That being said, the lag period is still there, even at higher temps. If you pitched the liquid yeast directly in, it'll take a little while to build up to the point that you see vigorous activity. You don't mention what sort of vessel you're using, but even if you have a carboy and you're looking for krausen, it can take a little while.
Also I'd check the expiration date for the yeast. That yeast is usually made available long before now and may be nearing the limits of its viability. Even at that, you'll see some activity soon unless something in the handling of the yeast completely killed it...but that's really highly unlikely.
I'd drop the temp, though.