Uneven watering is a useful clue. A little observation can make an irrigation service visit much more productive.
Notice the pattern
A single dry corner can suggest a different problem from an entire dry bed. Is the issue near one sprinkler, along a fence or across several zones? Does it happen every cycle or only occasionally? Write down the pattern rather than trying to diagnose every component.
Watch a normal cycle
If safe and practical, watch the system run through its usual schedule. Look for water hitting pavement, heads that do not rise, weak spray, continuous pooling or an obvious leak. Avoid adjusting unfamiliar controls or digging around buried utilities to investigate.
Check for changes nearby
New plants, settled soil and recent landscaping work can change how water reaches a bed. Plant growth can block a spray pattern that used to work. Mention changes to the garden, the type of system and the location of the shutoff and controller when requesting help.
Review the cause before changing the schedule
Running a struggling zone longer may waste water without correcting the cause. Have the problem reviewed, then revisit the schedule based on the plants, season and system. Watering should fit your property rather than follow a single timer setting for every garden.