Um… I hate to tell ya…yet, I must.
You can confess a sin all you like on the phone, but whatever confession you’re giving over the phone is not… cannot… and will never be the Sacrament of Reconciliation (a.k.a., the Sacrament of Confession).
P.S. I was a friend’s sponsor in RCIA a few years ago. In that particular parish’s RCIA program, there was only a brief mention that this is a Sacrament. I was appalled at that, but… there it was.
The supposition was that the enquirers’ own sponsors would cover that material with their person who was enquiring about joining the Catholic Church.
After all, as a sponsor you, yourself, are already a baptized and confirmed adult Catholic. In good standing, I must add. That means that you, yourself, as a sponsor have been to Confession more than once. And know all the necessary things to teach someone else about that Sacrament.
As an RCIA sponsor, it’s your role to fill in the holes for information that your person needs to know that aren’t yet covered in the RCIA program meetings.
For my friend, it took many personal sessions with her… here and there… to cover all the information. Some of it didn’t make sense to her (my bad in how clearly I presented the info, I’m sure). Parts made complete sense to her.
I told her… off hand… just guessing that she might be wondering but not asking me… that it’s just plain not possible to “go to Confession over the phone.” She was aghast that anybody, at all, would think that it even could be!