If/Else Statement + Custom Text

So I have this custom calc to auto populate phone numbers if a certain insurance is selected... but my insurance field is set to allow custom text for third party insurances. How do I add a code to allow for custom text to enter in a different phone number if a custom text is put in the insurance section? 

var fieldA = this.getField("Insurance").valueAsString;
if (fieldA=="BCBS Federal") event.value = ("1(800)442-4607");
else if (fieldA=="BCBS TX") event.value = ("1(800)451-0287");
else if (fieldA=="BCBS") event.value = ("1(800)676-2583");
else if (fieldA=="UHC") event.value = ("1(877)842-3210");
else if (fieldA=="Cigna") event.value = ("1(800)244-6224");
else event.value="";