Sometimes, without apparent reason, the client 'may' stop uploading or downloading data, without any visible error. When generating a HTTPS Debug Log (see: https://github.com/abraunegg/onedrive/wiki/Generate-https-debug-log-for-support) to determine what is going on, the failure that is generally seeing in this circumstance will typically be the following:

OpenSSL SSL_read: SSL_ERROR_SYSCALL, errno 104

This is indicative of the following:

• Some sort of flaky Internet connection somewhere between you and the OneDrive service
• Some sort of 'broken' HTTPS transparent inspection service inspecting your traffic somewhere between you and the OneDrive service

Reference: https://github.com/curl/curl/issues/4409#issuecomment-555715213

Further Reading:

• https://github.com/curl/curl/issues/4409
• https://github.com/curl/curl/issues/4624

The best avenue's of action here are:

• Ensure your OS is as up-to-date as possible
• Get support from your OS vendor
• Speak to your ISP or Help Desk for assistance
• Generate a support ticket with Microsoft and provide the HTTPS Debug Log

Additionally, to assist with diagnosing this issue further, please read: https://maulwuff.de/research/ssl-debugging.html