Cannot upload files bigger than 4 mb: net::ERR_HTTP2_PROTOCOL_ERROR

I get net::ERR_HTTP2_PROTOCOL_ERROR on chrome when trying to upload any file more than 4 MB.
On firefox, it does not show any http or http2 status or error message.
I have tried developer mode, bypassing the security and performance using firewall rule and using page rule, but it never works.
When I pause Cloudflare for the site, it works fine.
I am using Magento 2.4 and uploading downloadable products.
Has anybody else faced a similar issue?