The accounts I use are 4+ months old. You need to warm up the accounts with normal behavior to avoid potential bans.
Some people will just login to a new browser and start leaving reviews. This will get you popped as it's not natural. You need to sign into said browser, navigate to several different websites, sign up for some newsletters, add profile pic, add more profile information in your Google account, sign up for Google local guides, then only leave a single review the first day. Afterwards, slowly increase the amount of reviews you leave daily.
You need to keep using the same browser profile to make it seem more legit.
Anyone that needs recommendations should pm me.