A company spokesperson said in a statement that the changes were made on Sunday.
However, as a precaution, the matches on Sunday were also simulcast on the TVNZ DUKE channel.
Spark's head of sport Jeff Latch told the website Stuff on Monday that he believed that streaming for the rest of the tournament would proceed without glitches.
On 2 September, Spark said it had changed its plans somewhat before the tournament when it became clear that some areas of the country would encounter difficulties in streaming the content.
New Zealand is the current champion having won the cup in 2015 and also in 2011. An overwhelming percentage of the country follows the sport.
Spark said if customers had any issues with streaming, they would have the opportunity to watch on TVNZ DUKE.
In Australia, streaming service Kayo Sports experienced a few issues on Sunday which were sorted, as iTWire reported.
The RWC ends on 2 November.