2004 Grand Caravan P0700 Transmission Code: Causes and Solutions at 58,000 Miles

I've received a P0700 diagnostic trouble code on my 2004 Grand Caravan, which indicates a transmission issue. While I haven't noticed any noticeable shifting problems, the vehicle occasionally fails to enter reverse immediately—this doesn't happen every time but is consistent enough to be concerning. The van has accumulated 58,000 miles. I'm looking for insight into what might be causing this code and whether it requires repair or further diagnostics. Additionally, there's another specific transmission-related code (such as P1765) that I plan to verify soon and will update once confirmed.