I live in the boondocks, where internet connection can be...well...let's just say "not so good." While trying to keep my system (Buster) up to date, using 'apt update,' the reported download rates regularly vary between tens of kB/s to hundreds of B/s, to dead stop. Not surprisingly, apt eventually gives up and terminates with "...some index files failed to download." Also, usually, with "Undetermined Error" or "Connection timed out" followed by an IP address.
Is there a way to get apt to try again, without re-issuing the command in the terminal?