Validation tokens are how each social network understands that you have allowed a tool or application to receive data about connected accounts. They need to be always active so that sending this data through the API* of each network/channel is possible. This is the only way for reports to be generated without any errors.
The need to reconnect can occur when the account in question has had a password or other setting changed. But it can also happen due to the expiration of the access token. The tokens that allow us access to the networks are expiring more frequently than before. Mainly because of updates in the privacy issues of the social networks themselves.
The channels remove tokens after a while for user safety. This way they ensure that only the tools and apps that have their permission renewed will continue to have access.
*An API is a set of defined rules that explain how computers or applications communicate with one another. APIs sit between an application and the web server, acting as an intermediary layer that processes data transfer between systems. Each social network has its own API and documentation.
Any other questions talk to our support team via chat! Our office hours are Monday to Friday, from 8:30 am to 6:00 pm (UTC/GMT -03:00) América/São Paulo)