Hard to know what's going on without seeing your code setup and knowing more details, but it could be related to rate limits. You could consider using something like rotating proxies to help bypass some stuff. If you want to continue to use your own setup, you could integrate rotating proxies through a service. Dropping a link to one that we used for a couple of projects at my workplace.
[1] https://get.brightdata.com/bd-solutions-rotating-proxies