I tested my output water and it’s showing acidic, not alkaline

What are you using to test the water?  The pH strips used for urine and saliva can’t test water, nor can the yellow litmus paper.  You will need to use the pH reagent drops available here

Use the pH reagent drops to test your source water from the kitchen tap or bottled water that you have purchased.  Then, test the water from your alkalizer to see if there is a change in pH compared to the source water.

Please remember, if your source water is very acidic this will impact the final pH of the water.  Rainwater stored in plastic tanks is particularly acidic.