There isn’t a problem - we don’t normally get an ACK - there is the facility to do so but it is used rarely as gateways can’t hear on any of its 8 channels if it is transmitting.
Please read this: How do I format my forum post? [HowTo]
And you may find the following useful:
Read all of: https://www.thethingsnetwork.org/docs/lorawan/
The devices section of: https://www.thethingsnetwork.org/docs/devices/
The gateways section of: https://www.thethingsnetwork.org/docs/gateways/
The network section of: https://www.thethingsnetwork.org/docs/network/
The applications and API sections of: https://www.thethingsnetwork.org/docs/applications/