How can I extend my Single Entry Tourist Visa in Thailand if the owner of my accommodation is unavailable?

I have a Single Entry Tourist Visa from Italy valid for a Stay of 3 Month. I stay here 2 Month already now and want to extend the Visa at the Immigration Office for 1 more Month. I stay here in Suphanburi and the Immigration Officer says, that they need the ID Card and the Signature of the Owner of the Residence. I asked at the reception if the this is possible and everything looked fine until today. The lady at the reception says that the owner is in Bangkok. The Visa expires tomorrow. So what can I do now. Should I go to BKK for the extension? I come to Thailand every Year and this is the first time this has been asked to me.