Hi Enigma Cross
It doesnt matter that you worked those friends facilities 1 day ago, what it is taken into account is when you worked the last facilities before trying to work new ones.
To be able to rework friends facilities, you cant work any for 8 hours. If you continue working facs without waiting 8 hours or you enter to work again 1 second before the 8 hours then you will receive the oops message.
You can open both, facilities and services at the same time to work them, but there is always a difference of second or more between them.
Please, before starting to work friends facilities, open your own farm and click in the yellow tool box. Then click in Show times icon, the clock, and in Gamewide button.
If you have a green check mark for both, Rework Facilities and Rework Service facilities options, then you can start working without problems.
But if you see a time instead of the green check mark, then you will have to wait that time if you wish to rework facilities.
Everytime you work new facilities, the times in those options reset to 8 hours.