Kiwi syslog Messages not displaying

Hello Guys, sorry to bother but I am really struggling here and I don't seem to find any solution to this problem. 

I have a windows virtual machine in azure which is connected to a on-prem server of one of our client. Us and the client have kiwi syslog installed, and they are supposed to forward their syslogs to my virtual machine.They configured they on-prem server to accomplish this, but I do not receive any messages from them.

I run some extra test, I am able to run local messages and see them, I am able to ping my virtual machine (I cannot ask to our client to try the ping, because is disabled by default and they won't enable either for testing). The weird part is, if I go to "Inputs" and select "UDP"..I configure my port and the local IP..and if I press "Test" nothing happens, I don't see any output.

Some consideration that might help you to have a bigger picture, for now I have a free version of kiwi syslog. Might be this the root cause of this issue where I am not able too see any syslog messages from our on-prem client?

Please please, if anyone can help me I will be grateful because I don't know what to do anymore