Low score and wrong answer for Flan-T5-XXL "question-answering" task

I'm trying to run Flan-T5-XXL model for a "question-answering" task. Here's how I loaded and executed the model:

model_id = "~/Downloads/test_LLM/flan-t5-xxl"
tokenizer = AutoTokenizer.from_pretrained(model_id)
model = AutoModelForQuestionAnswering.from_pretrained(model_id, return_dict=False).to(DEVICE)

qa_T5XXL = pipeline("question-answering", model=model, tokenizer=tokenizer)

question = "What is 42?"
context = "42 is the answer to life, the universe and everything"

result = qa_T5XXL({
    "question": question,
    "context": context
})

However, I get a low score and a wrong answer:

{'score': 0.03840925544500351, 'start': 0, 'end': 2, 'answer': '42'}

Could you please help me make changes to achieve the correct answer? Thanks in advance.

from Low score and wrong answer for Flan-T5-XXL "question-answering" task