To keep your Visa status when you leave the country you need to purchase a re-entry permit. Do you really have a Tourist Visa that you paid for before you travel or did you enter for free on a Visa Exempt stamp?
In Bangkok at the main Immigration Office at Chaengwattana, Section C-1 issues the Non-O Visas and Section L-1 is for the corresponding 12 month Extensions of Stay (for Retirement, Marriage and Thai Child) plus the 60 day extension for Visit Thai Family. A Visa application costs 2000B and an Extension of Stay application costs 1900B.
Hopefully your Non-O was based on being married to a Thai and not on being over 50 as your first Extension of Stay must be for the same reason as the initial Non-O was issued.
Go to the online application and make very detailed notes of every requirement then ensure your application addresses every requirement in full and is supported with documented proof attached.
For your initial Non-O you will either need 800k in a Thai bank account in your name or an income affidavit from your Embassy (if they still provide one).