I wouldn't deduct them.  if you do next year you have to report the refund as income on page 1 of your 1040 (from schedule 1). 

Property taxes paid on personal property are entered on Schedule A as an itemized deduction.  Since the property taxes were refunded there is no need to report the property taxes paid on the 2021 tax return.

Additionally, if your Total Itemized Deductions on Schedule A Line 17 are less than the Standard Deduction for your filing status there is no need to enter itemized deductions on your federal tax return although, depending on your state, they may be needed on a state return, .

Standard deductions for 2021

Single - $12,550 add $1,700 if age 65 or older
Married Filing Separately - $12,550 add $1,350 if age 65 or older
Married Filing Jointly - $25,100 add $1,350 for each spouse age 65 or older
Head of Household - $18,800 add $1,700 if age 65 or older

And....you are not required to enter itemized deductions even if you have them.   So knowing that the property tax you paid will be refunded, it would make the most sense to just skip entering it on your 2021 return.

@susan-barnett - if you take the standard deduction, there is no impact here.  There is nothing to deduct and there is nothing to report as income.