Hi GettingHair,
Sounds like you’re using questionable tape and glue. These unbranded products (or re-branded) are inferior. Today’s quality tapes such as Super Tape and Walker No Shine tape are medical grade products and bond for 2 weeks and longer--even on oily scalps. A good bond is essential to looking good with a hair system. It may cost a little more but going with a name brand glue or tape is well worth it. You got started on the wrong foot with hair wearing but you can get back on track quickly. Here’s a stylist in London that can help you--tell her that John at Toplace USA send you:

Jo
Forever Hair
7 Goodwins Court
St Martins Lane
London
WC2N 4LL
United Kingdom