I don't want to convert my Xbox live gold pass to a game pass ultimate

Once you activated the Game Pass Ultimate your Xbox Live Gold was converted to Game Pass Ultimate time. If you cancelled Game Pass Ultimate, then you lose your Xbox Live Gold that was converted.

In short, once you have converted to Game Pass Ultimate, your Xbox Live Gold will be converted to Game Pass Ultimate. If you cancel, you will lose that converted Xbox Live Gold.

Yes the auto renewal is off already. I have the Game pass ultimate until May 25. I already bought a new 12 month xbox live gold card but when I try to redeem the code it says my 12 month
gold will be automatically convert to a 4 months xbox game pass ultimate which I don't want. I want the 12 month of xbox live without the game pass. Do I really have to wait until my xbox game pass expired before I can redeem a new xbox live gold (without
the game pass ultimate)?

There's a conversion rate when you swap from XBL Gold or Game Pass to Game Pass Ultimate, there used to be a limited time deal where it would convert it at a 1:1 ratio when Game Pass Ultimate first launched but I don't think that applies anymore. Before
you confirm the conversion to Game Pass Ultimate, it usually tells you how many months your current Xbox Live Gold subscription will convert to.

If you already have Game Pass Ultimate and want to use an Xbox Live Gold code then I think 1 month of Gold or Game Pass gives you 20 days of Game Pass Ultimate.

There's an FAQ at the following link, if you click on the question that says "After I join Xbox Game Pass Ultimate, can I still redeem Xbox Live Gold and Xbox Game Pass codes?" there will be a full conversion table: https://www.xbox.com/en-US/live/gold/upgrade

Unfortunately you would have to purchase gold again if that is what you want. Before purchasing the promotion, you are warned that whatever gold or regular game pass you have on your account will be converted to Ultimate Game Pass and cannot be converted
back.

Xbox Game Pass Ultimate:

Use your active Xbox Game Pass Ultimate membership to play games on Xbox One and Windows 10 PC. Xbox Game Pass Ultimate includes Xbox Game Pass for Console, Xbox Game Pass for PC, Xbox Live Gold and additional benefits. Note: Purchase of Xbox Game Pass Ultimate
automatically upgrades your existing Xbox Live Gold or Xbox Game Pass membership(s) to Xbox Game Pass Ultimate at a conversion ratio each based on days remaining. Learn how this works at www.xbox.com/gamepass. Future code redemptions are also subject to a
conversion ratio. Conversion ratio subject to change. All conversions to Xbox Game Pass Ultimate are final: Once converted, you cannot re-convert your Xbox Game Pass Ultimate membership back to a previous membership. Maximum 36 months of redeemed Xbox Game
Pass Ultimate per account at a time, including any converted time from Xbox Live Gold and/or Xbox Game Pass (for PC or console).