Testing

Hello everyone, 2 of our 7 Ultimaker S5 all on Firmware 7.1.3 can not be connected to our digital factory. They were connected last week but on the weekend all the printers got randomly disconnect. When pressing the connect button on the printers digital Factory Interface it just says that they are connected without showing any code and not showing up in the digital factory. With the other printers the same process reconnected them. Is anyone experiencing something similar and knows how to fix this? Thank you very much in advance!