Lawn issue

Hi everyone,
I have an issue with my lawn and I am really keen to understand what the problem may be. Over the past few days brown patches of dead grass are starting to appear on the lawn (see the photos) and I am not sure if I was too heavy handed with a spray of Praxys herbicide around 4 weeks ago, or if I have a fungal disease like Rhizoctonia.
Here are some photos and any help to diagnose and treat would be hugely appreciated.
Thanks
Stuart

 

What made you select Praxy as your choice of herbicide?

How was it applied, rates and did you spot weed or a complete coverage?

What was the weather like when you applied this?

When did you first notice the issues.

Did you apply any treatment before or after the herbicide?

If a knapsack or similar was used had this equipment been used for any other type of treatment”