Why I can't merge Deepseek R1 with Deepseek V3.1?

Both of these models is using same architecture and same model type, all same.

So, it won't be have any conflicts, but when I want to merge, it show "No output architecture found that is compatible with the given models". All supported output architecture: Mistral Deepseek MoE Qwen MoE Qwen3 MoE