Youtube API search videos max count

I'm trying to get all videos from Youtube channel using Youtube API.I'm using search.list query:

request = youtube.search().list(        part="id,snippet",        channelId="UC2sYit3cZ2CuD_8FHYH7O_Q",        maxResults=50,        order="date",        type="video"    )

Then, I use nextPageToken from the response and get all results from the next page.But, I can get max 500 videos and thats all, but the channel have 2293 videos.How I can get all videos from the channel? For example, video channel_id = 'UCnxmUrGMtpQT844Yd_l7Zyg'