Data in autofill entry not being populated in a target field

A telephone number field on a form that I use frequently requires a telephone number in the format “xxx-xxx-xxxx”, and the data in the autofill data contains a number matching that format. When autofill fills the field, the format is “xxxxxxxxxx”. Can you suggest a fix? I have tried several formats in the autofill data, but the results are always the same. Thanks.