Hello! Roleplay Hub as been having some troubles with MCPE; If it says 'Locating . . .' under the name you currently have for the server, you will have to wait until it says 'ROLEPLAY HUB' in purple text, it will not connect if you do not have that under it
Also, make sure the IP you are using is either mc.roleplayhub.net or pe.roleplayhub.net with the port 19132
If all fails, that means that PE is temporarily down, and you'll have to wait until it is functional again