Bought credits and didnt recieve them

Then it stands to reason that you were either scammed by someone who had hacked access to your device or bought the credits through a 3rd party middleman app.

3rd party middleman apps sometimes take around 3 weekdays to complete transactions despite customers seeing funds instantly being withdrawn from bank account.

Unfortunately if you were scammed by someone who had hacked access to your device that posed as a IMVU credit purchase webpage or similar then you will probably not get any credits. 

Lately there has been an increase in cybercrime and online fraud.

Think about creating a separate bank account that has a small balance available most of the time. At the start of each month a smaller amount is transferred to this account from main bank account. The purpose of this separate account is for online purchases which is why the balance of funds on it is small. Think of  this as an extra security layer that protects the main bank account from getting hacked. For this to work best then avoid net banking with main bank account. The main bank account is for in person transactions and any credit cards to main bank account are carried in a "Faraday cage" to protect the microchip from getting hacked via mobile phone WiFi. (This can be a thin metallic credit card casing that the card slides into or even a tinfoil wrapping.) If mobile pay is used often then consider opening a third bank account that has a medium sized fund available  The goal is to protect your main bank account.