UnicodeDecodeError: 'ascii' codec can't decode byte 0xc2 in position 2799: ordinal not in range(128)

[Raphaelzrf]

retriever = DenseRetriever(
index_name=self.index_name,
model="/data/rfzhang/harmfultext/model/sentence-transformers",
normalize=True,
max_length=128,
use_ann=False,
).index(collection, use_gpu=True)

When I run the above code, UnicodeDecodeError appears. I don't understand why it decodes the input in 'ascii'.