hi maybe a little trick
I have scaled x 10 the entiere model then made the fillet 0.2

I have not made the fillet base on this picture, but the fillet works also for the base!
(file 3Dm linked with base ;) (not unscaled / 10 !!! )

So you can "unscaled" / 10 at the end ;)
So I believe you work at a too little size scale of project unity ;)