Installed new battery, but macbook still shuts off

So I just installed a new battery in my macbook pro after the last one died after about 800 cycles. Before it died I could still use it with the AC cord plugged in, but if unplugged the computer would turn off. After I installed the new battery i'm still having the same problems.

I don't understand what's happening because when I check the battery status it says it's fully charged with a cycle count of 74 and the battery condition is normal.

When the AC cord is unplugged the macbook will shut off, sometimes when i plug it back in it will start right back where I left it prior to unplugging it, but other times it will just do a full restart. When I press the battery indicator (unplugged) to check the battery life nothing happens.

I've already tried resetting the SMC, although I'm not sure if i'm doing it right, because the light on the AC cord doesn't change when I hold shift+ctrl+option+power. If anyone could help me out It'd be greatly appreciated. Thanks in advance.