I'm in the process of moving into a P6 to replace my much-loved P3, because of the 3G switchoff.

Up till now I've used many of the Simple Mobile suite of tools, including the dialer.  But for the new phone, I'm giving the Fossify suite a try.  I'd really like to import my call history from the P3's Simple Dialer into the P6's Fossify Phone, but I'm getting "Invalid File Format" when I try.

It gets partway through the file (some calls are shown on the Call History afterwards), but working through the results of that to try and debug is not producing any useful clues as to what's wrong.

I've used a JSON file format validator to check there's nothing obviously wrong with the file format.  I'd like to try checking that the names (the LH part of each pair in the file) are valid, but I can't find anything about what Fossify Phone expects.  Does anyone here happen to know, or know where I could find it?  (Or have any other ideas as to what I could try?)  I'm a retired software engineer but very new to anything 'fancy' on phones.

Many thanks! 😀