Hi,
Simply removing the 16 from Teams Added in the second round should fix this.
With this input, it's trying to add 16 new teams that join at that round, on top of the 16 that qualify from the first round (ie, 48 teams total in the competition). Teams Added entries should only add up to the total number in the competition across all entries.
Alternatively, if you wanted those 16 teams to have a bye to the second round and only 16 teams take part in the first round, you need to change the first line to 8 matches and 16 teams added too.