Tru Green Lawn Care

First time in 32 years we got a lawn service and our front yard has never looked worse and it is so embaraseing! Back yard still looks good as we resodded that last year when we took out the pool. Aerated someone else's lawn by mistake, took over 2 weeks to come back to respray for weeds. Just did an experiment and used Weed be gone on a small corner of our front lawn and within 2 days the weeds are starting to turn brown so why can Truegreens not kill the weeds. They said that we have grubs (never had them before) and when I dug up some brown patches could not find one live or dead grub. The crab grass that they say that their products does not kill is now taking over my lawn and I have started to pull them out and reseed the areas.