Ulster have been hit with a retrospective one-point Pro14 penalty after failing to properly register new fly-half Ian Madigan for two games.
A Pro14 statement said that the club had not "received the correct documentation" from the Rugby Football Union for the former Bristol player.
This concerned the games against Connacht and Leinster in late August.
The matter was reported to the Pro14 before the Pro14 semi-final and final against Edinburgh and Leinster.
Madigan kicked Ulster's last-gasp winning penalty in the semi-final against Edinburgh although the Irish province were well-beaten by Leinster in the Pro14 decider a week later.
"One aware of the breach, the club immediately reported the issue and the player was correctly registered for the games played on 4 September and 12 September. The outcomes of the games had no bearing on the club's progression from the Conference stages," said the Pro14 statement.
"As this was a breach of the tournament participation agreement, it has been treated as an act of misconduct which the club has accepted.
"Pro14 Rugby accepts that this breach was not intentional and occurred due to an administrative error related to the furloughing of staff as a result of the Covid-19 pandemic."
Ulster have also been handed a suspended 10,000 euros fine which will come into effect if the club breaches any further player eligibility clauses during the 2020-21 season.