No connection Dietpi Raspberry Pi 4B

Hi!
I’m all new to this so bare with me if I did something obviously wrong.
I got a Raspberry Pi4 the other day. I flashed a 32 gb sd-card with dietpi and everything worked just fine so far.
Now, I have no possibility to use a monitor or mouse/keyboard, so my plan was to plug it into a switch and then use putty to complete the installation via ethernet on a pc in my LAN.
I went into dietpi.txt and set the static ip to one in my LAN range 10.65.10.13 plus network mask and gateway. Set the USE_STATIC to 1 aswell.
I plug the sd-card into the pi, connect the cable to the switch and start it up It starts up, the fan spind and the red light by the USB-C is red.
But, nothing show up in my client list for the router. Can’t ping it from my PC, cant putty into it. Nothing…
The port on my switch to which it is connected shows as disconnected. So absolutely nothing indicates that it’s anythingat all that my network can recognize? Anyone has any idea what I’ve missed?
I can’t feel the sd-card “spring” into place in the Pi but maybe the Pi4 card-slot doesn’t have that spring-type?

OK, I managed to get into the Pi. Out of a pack of 5 new out of the box short ethernet cables, I managed to use one that didn’t work…
Replaced it and all’s good.

Hi,

many thanks for your message. Indeed such thinks could happen. But good you found the broken cable.