Time machine could backup to cloud but cant now?

Hi all, please help, I have a cloud NAS drive which my MacBook Pro has been happily backing up to for the past year, now the last few days it says it cannot find the drive, try backing up when cloud is available.

I can access the cloud through the dashboard and from phones etc and get to the contents not trouble so I know the machine is working okay its just that the time machine cannot locate it, it tells me to select the drive to be removed but surely this means I would lose all the backups I have for the past year and have to start again, something I really don’t want to do.

I realise this is Apple and they are a nightmare but any help would be much appreciated as it driving me nuts!

@Trude1971 If you have a NAS then you should post in the sub-forum for the type of device you have. This is the sub-forum for the My Cloud Home-Personal Cloud Storage.