LFRS Rwy 21 ILS Frequency problem

Using my trusty B738 I set off to LFRS Nantes, all went well, until Nantes ATC changed the runway from 03 to 21. The ILS Frequecy is the same at both ends viz 109.90; I went to the FMC changed the Star and headed for the Rwy21 Approach, checked the Nav 1 and 2 frequencies were set at 109.90. Turning in on the rwy heading I waited for the Localiser to lock on, nothing, same deal for the GS; then 'ding dong' from the FMC, it showed 'disagree with frequencies'?? - OK we'll Go Around, next Approach, same thing, Go Around, by now ATC refused to speak to me (FS ATC) - so next time I solved the problem and hand flew the ac in.Question - does Fs9 have a 'history' for failed frequecies, or do I need to get Maintenance to check out the Radio? :)KenSomerset, England