error message - panicked at 'block hash not found in block index!' - using bitcoin core 25

[filipponeri]

Hi,

I am using bitcoin core 25 to download the blockchain data.
I get this error message when running

db = bq.BitcoinDB("/home/neri/.bitcoin/", tx_index=True)
[20:13:36] INFO - Start loading block_index
thread '' panicked at 'block hash not found in block index!', /root/.cargo/registry/src/index.crates.io-6f17d22bba15001f/bitcoin-explorer-1.2.20/src/parser/block_index.rs:125:18
Traceback (most recent call last):
File "", line 1, in
File "/home/neri/.local/lib/python3.10/site-packages/bitcoin_explorer/init.py", line 82, in init
self.db = _BitcoinDB(str(path), tx_index)
pyo3_runtime.PanicException: block hash not found in block index!

Any idea how to solve the problem?
Thanks, Filippo