Spotify's recently played endpoint seems to suffer some delays frequently, where:

• Listens show up many hours delayed
• Listens do not show up necessarily in order, e.g. a later listen can already been shown while an earlier will only show later

The second issue currently causes ListenBrainz to not import all listens. While the recently played endpoint will eventually report all tracks the missing earlier tracks do not get imported by LB once it has imported a more recent track.

Here is an example from my listenings today. This is the complete list of listens on Spotify for my account (in decending order):

• 2022-01-18T13:03:01.825Z: Shatter from Shatter - EP by Triptykon
• 2022-01-18T10:34:37.017Z: Our Voices Shall Remain from Our Voices Shall Remain by Throes Of Dawn
• 2022-01-18T10:28:01.497Z: Emperor from Gargoyle by Mark Lanegan
• 2022-01-18T07:57:22.975Z: The Greymen from Black Brick Road by Lake Of Tears
• 2022-01-18T07:52:19.788Z: Illwill from Illwill by Lake Of Tears
• 2022-01-18T07:47:58.183Z: Raven Land from Headstones by Lake Of Tears
• 2022-01-18T07:42:14.905Z: Calico from Crab in Honey by Fever the Ghost

The first two listens had been at 07:42 and 07:47.

At 14:07 the recently played endpoint only contained the second listen from 07:47 (see listens-2021-01-18T14:07.json). That means LB did not import the first listen.

In listens-2021-01-18T14:43.json also the listen from 13:03:01 shows up in recently played. But not any other of the listens, which causes LB to import only this last one.

Only at listens-2021-01-18T17:22.json all listens are present. But since LB already imported with a later time stamp they get ignored.