Issue with Excel word being replaced (HSA converted to HAS automatically)

I was having an issue typing HSA in Excel and it being constantly 'corrected' to 'HAS'. I literally could not type HSA, which stands for health savings account (HSA).

You can correct this by two steps: 1) Create the word in the custom dictionary and 2) remove the autocorrect option for HSA/HAS combination.

Step 1 - Add HSA to the custom dictionary

1. In Excel
2. File > Options (Figure 1) > Proofing > 'Custom Dictionaries' 
3. Select the dictionary you'd like to add the word to (Figure 2)
4. Click 'Edit word list'
5. enter 'HSA' in the word field 
6. Click 'Add' 
7. Click 'Ok'

Step 2 - Autocorrect removal for HSA/HAS

1. In Excel
2. File > Options (Figure 1) > Proofing >  'AutoCorrect Options'
3. Type the word you are trying to type (HSA for me) in the 'Replace' field
4. Look for the replace/with combination you are hitting (HSA/HAS for me)
5. Highlight the record, click 'Delete', then click 'Ok'

Figure 1

Figure 2 

Figure 3