Expected a map, got 'interface'

[du99cy]

This is a common function for create a item with given model and dto. The issue is summarized like the following:

• data has type of interface{} | dto.CreateDeliveryOrderDTO
• ins has type of interface{} | *model.DeliveryOrder

I want to decode from data to ins so that insert to database by GORM.
But I got a error expected a map, got interface. Any way to fix it for me? Thank you.