Unilox

Hey. My squirtle just got to level 16 and learned bite when the server crashed and went offline. When i got back in again i was rollbacked to lvl 14 again. So i leveled him back up to level 16 and nothing happend this time. So i continued to level to 18 And still he dident either evolve or had the chans to learn bite. How can i fix this?