Complete removal of secondary site!

Google removed all links of my payment gateway site

[dbansal]

I have 16 sites for different businesses. I am using a payment gateway linked from all pages of all sites.

I am targetting these 16 sites but from last 3-4 months, I am getting high SERPs, top 10 rankings not for my main site BUT for this

payment gateway site.

Today morning I wake up and saw all this payment gateway ranks in google are completely ommitted. I was getting good traffic

through it.

Although my main sites are under 100 in google, no tension, still what can be reason that stable rankings of 3-4 months, are completely removed? OR shall I wait for some days? May be they come back! OR shall I do something to get them back?

Advice me