iperf3 seems to be stuck after initial connection

Question

Yesterday, my tests with iperf3 were working fine. Today unfortunately it seems the initial connection is made but it freezes after that.

Below the outputs.

Server:

Server listening on TCP port 5201
TCP window size: 85.3 KByte (default)
------------------------------------------------------------
[  4] local 185.70.XXX.XXX port 5201 connected with 85.73.XXX.XXX port 55217

Client:

D:\Tools\iperf3>iperf3 -c 185.70.XXX.XXX -p 5201