if you use paid services, it's highly unlikely that you will get banned just because the sheer fact that you're using a VPN, on the other hand with free VPN services there's always a possibility, because those ips are abused to hell most of the time, just stick to the one(s) which work(s) for you, if you weren't banned throughout the months you were using a VPN service, you won't get banned in the future either, but all boils down basically to the following things:
is your VPN ip shared or dedicated? if dedicated and you're using it since months w/o any problem, that's good, if shared that still can be good, the question in that case: who you are sharing the ip with and what do they use it for?
on the other hand i think a dedicated private proxy is a better choice and is enough, there's absolutely no need to encrypt your whole connection via a VPN when using instagram
answering to your question in short: if you're using a blacklisted VPN ip, you can get banned, but the ban is instant, if you're using a VPN since months w/o any problem, you're good