Infinite "Thinking Mode" (CoT)

This is my first time downloading a local LLM through PocketPal, so maybe I'm missing something.

I turn on "Think" mode, type "Hello!" and the model ponders for 3-5 minutes about what to reply, then simply finishes its reply and doesn't write anything. Without this mode it responds normally. Is there any way to use this mode?

Qwen3.5-4B-IQ4NL and Q5_K_M on 12GB RAM phone