Some futons have spring-loaded locking pins on the arms to lock the backrest in upright or flat positions. Push them in and test each position.
Once all bolts are in place, go back and tighten everything fully with the provided tools. Over-tightening can strip threads — stop when snug. walmart metal futon assembly instructions
Since Walmart sells several models (Mainstays, Zinus, Better Homes & Gardens, etc.), this is a — always check if your specific model includes a model number or unique parts. Walmart Metal Futon Frame Assembly Instructions (General Guide) Some futons have spring-loaded locking pins on the