Years later and still got the exact same issue from time to time "Unable to update tracks". And as @zrod mentionned; having only one track that is generating the error is failing the whole batch addition. The result is probably having to do addition one by one wich is time and request consumming for us and YOUR servers too. Any fixes soon? Or at least ideas to what is going on?

I completely understand that for library tracks, if uploaded by the user. But I'm talking about "Apple Music tracks" here, these tracks from the Apple Music catalog directly. For example; I create a playlist on Apple Music. Then go in Apple Music catalog and add a track to this playlist. When then I'm retrieving this playlist tracklist with the Apple Music API, the ISRC field is empty while it's an Apple Music track. The issue is about why these Apple Music tracks (and not tracks uploaded by users) don't have any more the ISRC field ?

@_jb It's happening when you are retrieving tracks list from a playlist or from library of the user. When tracks are in a "list", the "isrc" field is no more returned.

Hi !I'm now instead of the previous message error getting:=> "Unable to update tracks" from the API when trying to add tracks to a playlist.Here is an example of a list of songs sent to have this error message :[{"id":"1045191907","type":"songs"},{"id":"1444873737","type":"songs"},{"id":"1081697965","type":"songs"},{"id":"1442277862","type":"songs"},{"id":"1064798417","type":"songs"},{"id":"1073169694","type":"songs"},{"id":"1445174755","type":"songs"},{"id":"1253076931","type":"songs"},{"id":"1098730576","type":"songs"},{"id":"1364129786","type":"songs"},{"id":"1445019394","type":"songs"},{"id":"1001771055","type":"songs"},{"id":"1440856655","type":"songs"},{"id":"1440834968","type":"songs"},{"id":"1319606196","type":"songs"},{"id":"1108737327","type":"songs"},{"id":"1496802229","type":"songs"},{"id":"726373148","type":"songs"},{"id":"1108987771","type":"songs"},{"id":"1170699703","type":"songs"},{"id":"1182107728","type":"songs"},{"id":"1254533944","type":"songs"},{"id":"1118431592","type":"songs"},{"id":"1050112236","type":"songs"},{"id":"1442215697","type":"songs"},{"id":"1398208561","type":"songs"},{"id":"1000069678","type":"songs"},{"id":"1444869589","type":"songs"},{"id":"1164239241","type":"songs"},{"id":"1120405215","type":"songs"},{"id":"1498632796","type":"songs"},{"id":"1374863253","type":"songs"},{"id":"1183998298","type":"songs"},{"id":"1452669850","type":"songs"},{"id":"1452670649","type":"songs"},{"id":"4332986","type":"songs"},{"id":"1116682200","type":"songs"},{"id":"1452623382","type":"songs"},{"id":"1129764619","type":"songs"},{"id":"1440620924","type":"songs"},{"id":"849428987","type":"songs"}]Any idea ? I can provide you more examples of lists like this which are generating the error.Thank you for your help.

Can't be sure for that, but the move here for Apple is just to there with Facebook Google And Twitter. So if you are not proposing one of them, I'm pretty sure that will be good for you 😉

Hi;Take a look here => https://developer.apple.com/app-store/review/guidelines/#sign-in-with-appleThe 4.8:Sign in with Apple is not required if:Your app exclusively uses your company’s own account setup and sign-in systems.It's required only if you are at least proposing Facebook Login, Google Sign-In, Sign in with Twitter, Sign In with LinkedIn, Login with Amazon, or WeChat Login.