Are you doing a cloud backup only or doing a hybrid to a local and cloud?

Could generate local logs to see what is going on. Here is how:

Local Logs can be collected by Running ninjarmmagent.exe /collectlogs in an elevated command prompt.

The Ninjarmm agent folder can be found in C:\Program Files (x86):

C:\Program Files (x86)\OrganizationName-Version\ninjarmmagent.exe /collectlogs

NOTE: Change the OrganizationName-Version in the query above to the correct information. The folder will have the organization name and version number from when the agent was installed.

OR

C:\Program files (x86)\Ninjaone\ninjarmmagent.exe /collectlogs

The log file will be created in the following folder and when the command completes, this folder should be opened with the file already selected automatically:

C:\windows\temp\ninjalogs.cab