If You made donation Offline (UPI, Check, Draft, Bank Deposit) then you have follow 2 steps to get 80G Certificate.
Step 1- You have to make a request for 80G certificate by entering following details -
Name, Mobile No., PAN, Bank Details, Amount and payment date.
Step 2- As & when you receive a sms of rediness of your 80G certificate then you can get it from here by entering reference number and mobile number.