Self feeding

Hi my child is 6 on the waiting list for an autism assessment. My child has no fine motor skill issues. My child can feed a doll, feed me by holding a spoon. My child can self feed as I have seen my child eating a few spoonfuls of food. My child has no difficulties holding cutlery or using them.

However, my child decides that for every meal they are not going to feed themselves. If I let my child be and didn't feed my child, my child would let themselves starve. My child won't go look for food nor self feed even when hungry. I have tried leaving my child too feed themselves, and my child just cries and won't feed themselves.

My child also has really bad reflux acid, so if I left feeding for long periods of time my child would be more difficult to feed.

My child eats blended foods. My child has no issues with the muscles in the mouth as this has been assessed.

I have tried feeding one spoonful and trying to get my child to do the next one but nothing. Even when I hold the spoon with my child, my child will not eat.

I have tried feeding my child's toy cartoon characters with the food and allowing my child to feed characters, but my child will still not self feed.

I have tried messy play with the food my child eats. My child will play with it but not eat it.

I know my child is delayed in speech and understanding so I'm wondering could this aspect also be a delay. This time last year my child wouldn't even touch any food. This year my child's touching food and chopping food even if it's not going to be eaten. 

My child has been seen by occupational therapy. They gave me strategies such as oral motor strategies which I've been doing but still no problems.

Any ideas why my child won't self feed and what I could do