Allowlists and a Happ subscription
An allowlist is an operator limit: only some addresses get through. Happ does not bypass that by itself. You need a server the network still allows.
What not to promise
“Works on allowlists” on every plan guarantees nothing. What matters is whether your subscription contains nodes that open from that network.
How to check
Import your link and look at the server list while you are on the restricted network. If locations appear, pick one that answers. If the list never loads, the subscription address itself is blocked, not the connect button.
HappSales puts the plan’s servers in the subscription. There is no magic “allowlist” switch on the site: read the list after import.
If it still fails
Refresh the subscription and check the term. If even the account will not open on that network, write to support with the operator name. A free public key is usually cut the same way.