There are a number of reasons the (charging) data in EEVEE is showing different information than for example the official app of your car, your charging station or the invoices you receive from charging stations.
Some of the causes could be
Temporary delay in sync
We are depended on the uptime and connectivity of car brand itself
There could be server maintenance on our side
In such case this is highlighted with maintenance banner in the app
Issue with caching or delay
First try to force close app and reopen
Log out and back in. A new import of all your car data will be triggered
Your car is not connected to EEVEE anymore
In this case you would need to reconnect your car via the Settings - My cars - + sign in the top right corner.
Impact
All of the above will impact the history in the EEVEE app, but also the .pdf report when generating it manually or when receiving it automatically by email.
Brand specific causes
BMW
car in ‘suspended’ state due to change of owner.
In this case you would need to reconnect your car via the Settings - My cars - + sign in the top right corner.
Tesla
The charging sessions in the app and invoices are rounded to an even number. EEVEE is showing the exact kWh charged.