No data to TTN-V3 from my devices

My setup: Home made 1 channel (LoRaGoDOCK) gateway and 3 different devices configured and registered for ABP.
Generated new device IDs and keys for TTN-V3.
However, I cannot connect to the TTN-V3 network, while that was no problem at all with V2.
Like some tips that I should look at to solve the problem…

That is not a valid LoRaWAN gateway and it should not be used with TTN. Not with V2 and not with V3. Because these single channel packet forwarders cause issues for other TTN users (please search the forum if you want to know why, it has been discussed numerous times) we do not offer any support for them on this forum.

Yes, go get a LoRaWAN GW - Single Channel & Dual Channel packet forwarders are not supported on TTN and should not be connected to the system as they are disruptive to other users and cause problems as you are now finding… Please disconnect it.

OK sorry for that! I did not know that and I will read the forum for the reasons…
I have disconnect the gateway and will search for a LoRaWAN GW.
Thanks for info!