"Some responses to the consultation were received as blank so we have contacted those people affected and offered them the opportunity to resubmit their comments.
"If anyone had difficulties submitting the form we will still accept their responses.
"This was an open consultation and we have worked closely and cooperatively with a range of leaseholder organisations, including the NLC."
A source close to SurveyMonkey said it was not aware of any technical issues which would interfere with the collection of submitted responses to the government department's consultation.
The most recent consultation on leasehold reform follows an initial consultation in September 2017, which received more than 6,000 responses with the majority in favour of widespread improvement.
Ms Kendrick added: "The NLC is concerned this second consultation was never needed given they had 6,000 responses to the first consultation.
"We are worried this second consultation is moving away from a peppercorn ground rent on all new build leases which will have a damaging impact on the move to common hold."