Sinn Féin had to submit records of its 2020 General Election expenses to the Standards in Public Office Commission three times, according to documents released to Fine Gael.
Sinn Féin says it is compliant with SIPO and it has branded the latest revelations as an attempt by Fine Gael to distract from the controversy around Minister for Public Expenditure Paschal Donohoe.
He will make a Dáil statement on the matter in Dáil on Tuesday, but is also likely to address the issue publicly either tomorrow or Monday.
The Fine Gael claim follows Sinn Féin's updating of its election spending to take account of a €7,000 opinion poll it paid for during the 2020 General Election campaign.
The party did not include this in its first spending return to SIPO in 2020 but it did so last year.
However, the documents released under Freedom of Information show "difficulties with the totals" provided to SIPO in 2022.
Fine Gael Minister Peter Burke has called on Sinn Féin to "explain everything".
"The Standards in Public Office Commission (SIPO) directly told Sinn Féin last year 'there are difficulties with the totals' it had furnished as part of an updated 2020 General Election return the party was forced to make after a media query - and that some of its amended election returns were 'incorrect,'" he said.
Sinn Féin decried the Fine Gael call as a desperate attempt to distract from a "serious controversy surrounding a political donation worth thousands of euro given to Paschal Donohoe by developer Michael Stone."
A party spokesperson said: "Sinn Féin is fully compliant with SIPO and SIPO have accepted our amended declaration."
They said an issue arose when an invoice for a poll published by Sinn Féin during the 2020 election was omitted in error from its election returns.
"This was an invoice paid by Sinn Féin in Dublin. When this error was brought to our attention by a journalist we immediately informed SIPO and amended our declaration," they said.
However, they said the amended declaration had included an "earlier version of one of the pages" rather than the final document submitted in 2020.
"This was resent to SIPO and they have accepted this," the spokesperson said.
"It would be much better use of Fine Gael's time for Paschal Donohoe to come clean," they said.