Internet with LAN cable in the switch slowly?

Fa
- in PlayStation
1

So, I have a Lan cable from the Fritz box moved to my room, and then there in the switch and with 2 more cables in the console and PC. That went well for 7 months, but then my internet was completely slow and I can't do anything anymore. If I put the Lan cable of the Fritz box then directly into the Pc or Ps4 again everything works, but if only in the switch it is not again. New and other switches we have tried, but nothing works. We then discovered that the plug of the Lan cable was completely oblique, and we will make a new plug on it tomorrow, but then I think again if I put the cable directly into the PC or PS4, yes.

Does anyone have suggested solutions? Would be happy about every tip.

Sy

And, what has happened?