Hi. We struggle all the time with ours. Mainly where the sprinklers weren’t placed well. We usually water those spots with hose for a while to see if it’s drought. But it wouldn’t hurt to send pictures to your installer for advice.

Looks like it's been overwatered to the point that it now has a fungal disease. Your pictures are not close enough to see lesions on the grass blades, but if the grass looks like this...

...then the solution is to apply ordinary corn meal at a rate of 20 pounds per 1,000 square feet over the entire lawn. Yes, I realize that corn meal does not sound like a solution to fungal disease, but please humor me and do it anyway. I resolved my disease issues in St Augustine with corn meal for 20 years, and it worked every time. I have not had the issue at our new house...yet. Corn meal is a biological control for disease, but it only seems to work in St Augustine. I've been on this forum since 2002 and have a lot of experience with this treatment. I originally had hoped it would be a universal cure for all lawn disease, but it really only does work on St Aug. You can get corn meal in 50-pound bags at your local feed store. Call first for availability and pricing. If they quote a price of $30 per bag, they are talking about another product called corn gluten meal. Ordinary corn meal should be around $10 per bag or less. After you apply you may see birds hanging out in the yard. That's fine. There's no way they can eat as much as you applied + they leave droppings and eat insects while they are there. It's a win if they come. Corn meal takes 3 full weeks to see the new grass coming in green and remaining green, so don't get frustrated after 2 weeks thinking it won't work. Oh, and if you apply a fungicide first, then corn meal really will NOT work. It must have normal biology in the soil to work.

Your lawn looks mature enough that you should be watering it roughly once per week in the summer. If you live where the daytime high temps are in the 80s, then you could get by with once every 2 weeks. If your temps are in the low 100s, then once every 5 days should be enough. Water deeply which means 1 inch all at one time. You can time your sprinkler system to know exactly how long to water. Place some tuna or cat food cans around the yard and turn on the sprinklers. When the cans are full, that's your watering time from now on. After you know that then all you have to do is vary the frequency. With temps in the 70s water every 3 weeks. If you get rain, then reset your frequency calendar and water again when the grass seems to need it.

I think it’s dead? What on earth did I do wrong? Or did the installers do something wrong. It looks like straw in many patches of my lawn. Over water? Under water? Stepped on too early? We thought we followed everything to a T.

I was watering three times a day for a month…

I’m not a grass expert by any means, but my dad’s newly sodded St Augustine and Bermuda looked like this due to Army Worms. They wiped his entire lawn out within days. It happened to us with established Bermuda the same year.

I’m thinking you’d see the worms themselves, though, so it’s probably not that. Just thought I’d throw it out there because it looks so similar.

Good luck, I know it’s frustrating.

ETA: Just remembered that we got them later in the summer, in August, so now I really doubt they’re the culprit here. Ignore me. :D

I think we started with 20 minutes and moved down to 12? I’ll have to double check with my husband but my water bill is massive so i find it hard to believe I under watered.

I knew I should have invested this money in a new kitchen. What a pain this is… thanks for your responses!

Under watering is almost never the problem. After 2 weeks the grass roots should have been knit to the soil and you could have backed way off on the frequency. After a month I would expect you to be watering at most, twice a week. If you'd done the tuna can test you would be closer to understanding whether you over watered or under watered.

Yes the grass blades are dead, but it seems the roots are still trying to push up new grass. It is recoverable without bringing in new sod. In fact with a disease in the lawn, bringing in new sod won't do anything except kill the new sod.

I have one side in my backyard that looks like yours, straws. I plan on adding corn meal like someone mentioned here and see. I have St. Augustine.