You have two-way binding and you have not input anything. Then your printSingle.szLat is undefined.
If you need an empty string for "", you can initialize it
data () { return { printSingle: { szLat: '' } } }
The variable is defined, but when there is no value, the value is undefined
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You have two-way binding and you have not input anything. Then your printSingle.szLat is undefined.
If you need an empty string for "", you can initialize it
The variable is defined, but when there is no value, the value is undefined