Child hates parks and walks but loves shops.

Basically I'm asking if anyone had these situations before. Our 2.5 year old toddler with asd used to love walking around parks and different places outside. Now every park in our city and cities next to use that he absolutely used to love, he hates them now. We can't even get out of the car because he has complete meltdowns. Nothing changed neither the parks, nothing bad happened in them, no different shoes, just out of nowhere for some time now. On the contrary when he sees we're going to a shop, shopping mall or anything where you can buy something, he's an angel. Helps putting things in the basket, walks holding my hand basically a different child. We took a short walk around the block just to see how he would react. He walked around the blocks hundreds of times, but he had a huge panic attack and started screaming that he couldn't even calm down at home and took like 10 minutes for him to stop crying. I'm sorry if this post is all over the place English is my second language and I'm really ranting here. Has anyone had situations like this? Any help?