Both are fine.
As is often the case, the difference is not an objective one, but lies in how the speaker wishes to present the temporal nature of the events described.
I still receive is normal and neutral. I am still receiving emphasises the continuing nature of your receiving parcels. In both cases still marks that it hasn't changed with the changing circumstances.
On another subject, you have a run-on sentence, because there is no grammatical relation between your two clauses. Without an inversion in the first clause, However reads like a sentence conjunction (like a stronger "but"). I suspect you mean However fast COVID is speading, in which however acts as a subordinating conjunction, and the whole clause reads as a concessive subordinate clause.