Hi @MichelaRiba, sadly there have been quite a lot of changes in the last 5 years with regard to microbial taxonomy. Each curated database can vary, and use different nomenclatural rules.
Fortunately, we've made it easier to import a few via various QIIME 2 tools and the RESCRIPt plugin. Aside from SILVA, you can make use of:
RESCRIPt also has some tools by which you can compare these.
-Cheers!
-Mike