Soft, droopy leaves after repotting

[rosslyn1037]

Hi, I recently repotted two of my Phal orchids (one about 3 months ago and the other about 1 month ago). The leaves on the first one I repotted went a bit soft and droopy, but still has not firmed up. I thought it would by now, after adjusting to its new pot. The other one has the same problem. The lower leaves are the ones that are especially soft on both plants, but not turning yellow. Other than that, the plants look fine. Is this normal behavior after repotting?

The potting mix is a bagged mix especially for orchids, made up of bark mulch, charcoal, and perlite. There was no sphagnum moss in the mix and I didn't put any in the pots, which are clay. Could it be that they are drying out too quickly? Should I get some sphagnum moss and repot them again, or would this really hurt the plants? I water about once a week. Maybe I should water more often? I just don't know what to do. I don't want to lose these orchids. Can someone out there who is an expert advise me about this issue? Thanks so much!