If you filed and paid for your 2551M for any month in the taxable year 2018, that was a mistake. :( You should've filed using a 2551Q instead. This is based on an advisory that the BIR released earlier this year.
If you filed through Taxumo, you're lucky. :) We were able to align a process with the BIR for forms & payments submitted through Taxumo - those users will get a refund. If you're one of those lucky users, please note the following:
If you paid via Paypal, you will get the refund via Paypal.
If you paid by any other means (Dragonpay), please do share with us your preferred bank, account name, and account number. We will be able to refund to you through any major bank (Unionbank, RCBC, BPI, BDO, Metrobank, PSBank, DBP, Landbank, and Chinabank).
We can also provide the refund thru GCash, just send us your mobile number.
Do note please that the gateway fee has already been remitted to the gateway so that will not be part of the refund. If your bank has any charges, that will be taken from the refund amount as well. Email us at customercare@taxumo.com with your preference. :)
As for payments/filings made outside Taxumo, the BIR did not release any instruction on how to deduct those payments made. That means that you will likely have to go through the formal tax refund process to get that amount back. It's a bit of an ordeal so we recommend that you call the BIR Contact Center @ (02) 9817003 to find out how exactly that is done.