Our centre-half spoke to iFollow Barnsley after a 2-0 defeat at home to Exeter City on Saturday at Oakwell.
A Jay Stansfield brace for the visitors meant the Reds were defeated for the first time since August after recently winning three on the spin.
Cundy didn't believe the team were at the races on the day and made the task at hand more difficult after conceding early on.
"Not good enough really, from everyone," he stated. "Obviously, the start sets the tone, conceding within five minutes. It's always a big hill to climb, but I just think as a group we weren't at it."
The fundamentals of what saw Michael Duff's men go six unbeaten in the league and climb to fifth in the table were not there against the Grecians, in the opinion of the 25-year-old.
"Their goal killed us a little bit," admitted Cundy. "But as a team, we weren't doing our basics well. The likes of pressing, squeezing up, second balls. It wasn't really there for us for some reason.
"That's just one game, we've got 30+ games left to go. We'll make it right."
Despite having numerous chances and plenty of possession in the game, the Reds were unable to breach the Grecians defence at Oakwell.
Cundy emphasised that even though it was a disappointing afternoon for everyone in Red, the team must pick themselves up and focus on the challenges ahead.
"We had a few chances in the first half. In the second-half we had a lot of the ball and they were kind of sat in, playing on the counter.
"It's about being ruthless in both boxes. We've got to park this one up behind us and move onto the next. We've got a game Tuesday, and then Saturday as well obviously.
"We've just got to make it right in training and correct this performance."
The game against Exeter marked the quarter stage of the league campaign, playing 12 games and lying in fifth.
Taking a wider perspective, Cundy believes overall it has been a good start to the season considering all factors at play.
"I think it's been good.
"It's a new group and a new gaffer, so it's going to take time to gel together. I think we've done well. We've maybe been a little inconsistent with performances, but obviously like I said the last five games unbeaten.
"It's there, we've just got to tick off our basics every week and from then on we'll be ok."
