Getting 2.4 security cameras to sync to wifi

I owned our previous "gateway."  It stopped working, so went to Xfiniity and got THEIR gateway.  Hooked it up, and gave our 2.4 and 5 bands new names.  Now our security cameras, which are MOUNTED 20' HIGH don't connect.  I wonder if i rename our 2.4 band the original name that the security cameras were used to might solve the problem.

Any ideas?  This change-over has been INCREDIBLY frustrating and time consuming, took about 2 hours with tech support to get the new gateway to work and to get our two landlines running.

I'm not looking forward to any more difficulties.