@bhhussain
Hi. It seems that you have trouble with the VLAN tagging/untagging.
You should check out the Wired Networks > LAN > Networks, create your VLAN first. If you have multiple VLANs, make sure you create them all.
Then, to the Profile. Create one and select the VLAN networks as tag/untag. Since you mention you have core switch, I think that you tag the port on your core switch. Is that correct?
Supposedly, the map should be: CoreSwitch_port# X[tagged_VLAN10 20 & 30]----OmadaSwitch_port# X[tagged_VLAN10 20 & 30] (I am giving an example)
Exam your profile. You can create one and name it Trunk. Or you can just use the "All" profile. Make sure you check the VLAN10 20&30 in the "Tagged Networks".
So, this profile should goes to your OmadaSwitch_port# X. X is your port.
Till now, you have made sure that your uplink to the core switch is good. If you have other devices like APs, you create the profile accordingly. Or you can use the same profile which can give you VLAN10 20&30 networks to the AP.