URL Formula Add Button Not bringing bringing over info from Parent

Can anyone tell me why this URL add button formula is not bringing over the Record ID to reference field in the new child record AND it's not bringing other desired info: (I have triple checked the fid's.)

URLRoot() & "db/" & [_DBID_PROPERTIES] & "?a=API_GenAddRecordForm&_fid_755=" & URLEncode ([FMLS#])&"_fid_28="&URLEncode([Full Street Address])& "_fid_30="&URLEncode([City])& "_fid_31="&URLEncode([State])& "_fid_32="&URLEncode([Zip Code])& "_fid_71="&URLEncode(

)& "_fid_34="&URLEncode([County])& "_fid_35="&URLEncode([Lot])& "_fid_237="&URLEncode("Manual MLS Research")& "_fid_798="&URLEncode([Status])& "_fid_51="&URLEncode([Year Built])&"_fid_47="&URLEncode([Square Footage])&"_fid_105="&URLEncode([Unit Number])&"_fid_40="&URLEncode([Parcel Number])&"_fid_52="&URLEncode([Total Bedrooms])& "_fid_39="&URLEncode([Subdivision/Complex])&"_fid_36="&URLEncode([Block])&"_fid_24="&URLEncode(
)&"_fid_53="&URLEncode([Total Bathrooms])& "_fid_342="&URLEncode(
)& "z=" & Rurl()

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George Bramhall
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