you can buy a new base but when you buy all the options at your current base.. e.g health,economy level,mens,sentry level e.t.c e.t.c,, updgrade all of them, then collect the diamonds to buy your next base.. when all the upgrading are done, then see your right hand there will be pic of base written : New base tier 2 or 3…
hmm try checking your weapons,, because levels need upgraded weapons, for this purpose you will need to earn diamonds or buy golds.. when base upgrade is completed, then get another base,, and you will update it moreeeeeeeeee.. i hope you get it