LoadLibrary function.mprotect if necessary. Also, make sure the stack is 16-byte aligned before calling LoadLibrary to meet the x86-64 ABI requirements. Verify that NASM correctly encodes the push instructions by checking the output with a disassembler, and ensure you are using the correct assembler and linker flags for 64-bit mode. Debugging with a tool like gdb can also help trace the execution and confirm that the 64-bit values are pushed correctly onto the stack.