Question
I have a weed control service that comes every six weeks but I still have all kinds of weeds in my grass. We have had a lot of rain almost everyday, could this be the cause of all the weeds. Thank You In Advance

Answer
Your weed control service treats every six weeks. Many weeds can complete their life cycle (germination to seeding) in a shorter period. So by the time the service treats again there will be weeds in various stages of growth. My experience has taught me that once a calendar month is a good schedule. It is possible that the service applies a pre-emergent (germination inhibitor) product. You will have to ask them. If 'yes' then newly emerged weeds should not be a big problem.
In general, a chemical is designed to correct a specific problem. Pre-emergent weed control; emerged broad-leaf weeds, emerged sedges and things like that. If the product appears to be ineffective, then it is a problem with the rate (oz./1000 sq. ft.); coverage (gallons mixture/1000 sq. ft.) or weather conditions around the time of application (rainfall, drought stress, cold  temp.) and things like that.
Hopefully, you will find this answer useful.