Errors when setting Channel Limits in bulk

Hi all,

Newbie to PRTG so apologies if the questions seems trivial to you.

I have created a Library for (example) SQL Servers. I want to adjust all C: OS drive to Warning Limit of 5GB and Error Limit of 2GB Want to set non- OS drive Warning to Warning Limit of 10GB and Error Limit of 5GB.

Steps I am taking:

1. I go to Sensors > By Type > SNMP Disk Free
2. Use Filter and use my SQL Tag to Disks for all my SQL Servers
3. I only choose C: OS drive and click on the right to select all my SQL Server
4. Go to Setting (Spanner icon) > Channel Setting > Free bytes (ID 1) > Limits > Enable alerting based on limits.
5. I set "Lower Warning Limit (MB)" to 5000
6. I set "Lower Error Limit (MB)" to 2000
7. Set my Warning and Error Messages.
8. Click OK .

I get error as below:

Error (Bad Request) The Validation of the data you entered has failed. . Channel 0 (Free Space): You have set Alerting to limit-based, but have not entered no limit value

The object has not changed. Error Details:

Version: 21.3.71.1416
Server: akprtgsvr01.stjohn.org.nz
URL: /editsettings?channel=1&want_limitmode=1&limitmode_1=1&want_limitminwarning=1&limitminwarning_1=5000&limitminwarning_1_factor=9.5367431640625E-7&want_limitminerror=1&limitminerror_1=2000&limitminerror_1_factor=9.5367431640625E-7&id=49818,49379,13849,50648,14536,12615,50571,14149,13910,13665,14452,14524,12762,48310,13926,14146
Time: 16:11:37

Anyone can help me with this, not sure what I am doing wrong.
Are there any pre-requisites in need to do before doing bulk Limit changes like this?
I tried the same process on only one SQL Server OS C drive and it worked without any issues.