I know the password to my work Wi-Fi network but it won't let me connect?

One day I successfully connected my phone to it, but no other devices would connect. Now my co workers iPhone will connect but my phone won't anymore. I'm thinking it's either mac filtering or a limited number of IP addresses. It's a draytek router. I'm permitted to use the network but like I said I can't connect anymors?

Please Restart your Wi-Fi Modam after that you check it it will be work very fine