[BUG] /val/match/v1/matchlists/by-puuid/{puuid} Returns inconsistent number of matches per player with varying earliest dates

[StabbedToDeath]

Bug Description
We have 3 accounts with greater than 100 matches in the past 2 months. And /val/match/v1/matchlists/by-puuid/{puuid} endpoint returns 85 matches for 2 players with the earliest dates of the matches being August 29th 2023 and August 17th 2023 respectively. For the 3rd account, the number of matches retrieved are 95 and the earliest date is July 23rd 2023. Note that all these accounts belong to the same region/active-shard.

Problem Description
Due to this inconsistency, I'd like to know if there is a hard cap on the number of matches retrieved or if there's another factor that decides how many matches are returned as they don't seem to be capped by the date of the games played as well.

Expected Result
A fixed amount of matches regardless of total number of games played unless games played is less than the fixed amount.

Actual Result
Inconsistent number of matchIds returned per player.

[geozukunft]

I don't use the VAL endpoints but could it be that the "missing" games are like custom games that are not publicly available?

[StabbedToDeath]

One of the accounts that was used to test this was mine and I do not have any hidden custom games. We also made sure to test queue dodges and remakes, but those games also didnt seem to affect the number of responses.