Can you please provide the full commands you used, as well as links to the datatbase you're trying to import?
As for the SILVA LSU... I'd suggest installing the latest version of QIIME 2 (2024.10). There, you can use RESCRIPt (now part of the QIIME 2 install), and follow the SILVA RESCRIPt tutorial to import the latest SILVA (138.2) LSU database. You can modify the database you download like this:
qiime rescript get-silva-data \
--p-target 'LSURef_NR99' \
--output-dir SILVA_LSU_138.2
-Cheers!