I performed 10 transactions in Maxis Pay, with my Public Bank Quantum MasterCard, around 2 to 4 am on 11th December 2017 (Monday). It is the first day of Week 20 for "Get Rewarded with PB Cash" Campaign.
After that, I called Public Bank Credit Card Customer Service Hotline to obtain the time of transaction, as captured in Public Bank System.
By comparison, the time of transaction between Maxis Pay and Public Bank System is almost same, perhaps with a difference of about 1 minute.
The weird thing is that as seen in the transaction history of my credit card in Public Bank Internet Banking website, the date of the 10 Maxis Pay transactions is 10th December 2017 (Sunday).
Does that mean that the 10 Maxis Pay transactions are not counted for Week 20 for the swipe campaign? But, the payment gateway for Maxis Pay should be in Malaysia, and in the same time zone as us. It is not some online websites, such Lazada, whereby its payment gateway can be in Europe or America.
Should I call Public Bank Credit Card Customer Service Hotline, to request the date of the 10 Maxis Pay transactions to be amended to 11th December 2017 (Monday)?
Thank you for the advices given.

You can preemptively call. When I kena that for shopee I called after receiving less cashback, they amended later on.