In John 20:17, Jesus uses the present active, 1st person singular
anabainO, "I am ascending" and that's apparently His reason to say to Mary that she should stop clinging to Him. As He was ascending, it seems it was a problematic time to be among those that had not yet been resurrected/given new, heavenly bodies (See II Cor 13:35-49).
Secondly, Jesus had a ministry to those in prison, as is noted in 1 Peter 3:19, He went and made proclamation to the spirits now in prison, almost certainly during the time before he was fully ascended to the Father.
He was busy where He could do the most Good.
Oooops. Typo. That was supposed to be I Cor 15:35-49, not II Cor 13.... Sorry