hmm ... every 4 days may not be too often - or it could be - depends on multiple factors. A skewer in the potting media, as Cheryl suggested, is very helpful.
The flowers wilting could be just that they were naturally at the end of their life. This type of orchid also can be prone to some black spotting on the foliage. If you post a few more times, you can post some photos, which would help members to see if it looks serious or not.
Once the flowers are done - pull the plant out of the pot to see how the roots look. That would also be a good time to repot.