Oil change, without the sticker
The windshield sticker only helps if you look at it. A text does not require you to be in the car.
Time vs miles
Many modern oils are good for 5,000–10,000 miles. If you do not track miles, a 6-month reminder is a safe default for mixed driving. Put the oil type in the message if you DIY.
After the change
Complete the reminder from the text. For a once reminder, that frees the free-plan slot so you can set the next date.