I think I have more than needed Activity and Merits to be a Sr. Member... why is it not being updated?

You meet the Activity requirement yes, but you are falling short in Merit. You need 250 merit to be a Sr. Member and as of now, you only have 56.
I see... well looks like it's going to take me forever to get promoted since it is hard to get merits. Can you perhaps suggest me how I can get more merits? Thank you in advance.