The Lord is so kind to His devotees that He took all the responsibility for the doormen's offense and requested the sages to give them facilities to return to Vaikuntha as soon as possible
SB Canto 3
These servants of Mine have transgressed against you, not knowing the mind of their master. I shall therefore deem it a favor done to Me if you order that, although reaping the fruit of their transgression, they may return to My presence soon and the time of their exile from My abode may expire before long.
From this statement we can understand how anxious the Lord is to get his servitor back into Vaikuṇṭha. This incident, therefore, proves that those who have once entered a Vaikuṇṭha planet can never fall down. The case of Jaya and Vijaya is not a falldown; it is just an accident. The Lord is always anxious to get such devotees back again to the Vaikuṇṭha planets as soon as possible. It is to be assumed that there is no possibility of a misunderstanding between the Lord and the devotees, but when there are discrepancies or disruptions between one devotee and another, one has to suffer the consequences, although that suffering is temporary. The Lord is so kind to His devotees that He took all the responsibility for the doormen's offense and requested the sages to give them facilities to return to Vaikuṇṭha as soon as possible.