First you will need to export your current termbase by following this KB article:
How do I export a termbase from the Termbase Management view in MultiTerm Desktop?
NOTE: recreating a termbase will not keep the individual termbase user permissions. These are called
Roles in pre GS 2017 and
Restrictions after. It will also not keep any objects, filters, etc. So those will also need to be recreated manually.
If you want to keep your old termbase, you will have to create a new one from that export and give it a different name. Otherwise, you can delete the old and create a new one. Here is how to do that:
How do I create a GroupShare server termbase from .XDT and .XML files?