TryParse error with set_security_group

[cdriess]

Describe the bug
Since several weeks, when using the set_security_group action, the task send the following error:
Exception calling "TryParse" with "2" argument(s): "Cannot convert null to type "System.Guid".

the used yaml

pool:
  name: ASSYST agent pool

name: $(Build.BuildId)

trigger: none

variables:
  - group: 'BC-SaaS-Config'

jobs:
- job: Create_Sandbox
  displayName: 'Create $(bc_deployment_environment) from $(bc_production_environment)'
  steps:
    - checkout: self
      clean: true
        
    - task: ALOpsAdminCenterAPI@1
      displayName: 'Set security group'
      inputs:
        azure_tenant_id: '$(azure_tenant_id)'
        azure_app_client_id: '$(azure_client_id)'
        azure_app_client_secret: '$(azure_client_secret)'
        interaction: set_security_group
        environment: '$(bc_deployment_environment)'
        security_group_id: '$(bc_deployment_security_group)'

    - task: ALOpsAgentMaintenance@1
      continueOnError: true
      condition: always()
      inputs:
        removeoldtasks: true
        removebcartifacts: true

the output
Also the complete output is necessary for us to see what is going on. Also use backtics:

Version      : 1.474.10523
Author       : Hodor
Help         : Interact with BC SaaS AdminCenter API.
==============================================================================
*** Validate configuration
*** Task Inputs:

name                                  value                                   
----                                  -----                                   
azure_tenant_id                       a379d***-****-****-****-************    
azure_app_client_id                   0dba4***-****-****-****-************
azure_app_client_secret               ***
azure_app_client_certificate                                                  
azure_app_client_certificate_password                                         
username                                                                      
password                                                                      
checksecondsdelay                     30                                      
maxtries                              20                                      
interaction                           set_security_group                      
wait_for_operation                    True                                    
environment                           Deploying                               
target_environment                                                            
target_environment_type               Sandbox                                 
use_update_window                     False                                   
app_id                                                                        
accept_isv_eula                       False                                   
force_dependencies                    False                                   
confirm_delete_data                   False                                   
application_insightskey                                                       
security_group_id                     29ff5***-****-****-****-************    



True
*** For documentation, please visit   : https://www.alops.be/documentation

*** ALOps License:
  * Licensed To: Assyst-Europe (Per Run License)

*** Imported required PS-Functions
*** Parse Task Parameters
##[error]Exception calling "TryParse" with "2" argument(s): "Cannot convert null to type "System.Guid"."
Finishing: Set security group

Expected behavior
The task sets the security group without error.

Screenshots
Not applicable

Additional context
The first time we got this error was on the 30 of january.
The last successful run was on the 19 of december.
Other pipeline like the copy of the production works without error.