Having problem bonding Ipaq PocketPC with Motorola V550

I have a HP Ipaq 4700 PocketPC as well as a Motorola V550 phone. I
have had both of these for around a year and I have bonded the two
since I use the phone tethered with the PocketPC to use internet
through the bluetooth. This has worked fine for a year.
The problem I have now is it simply won't hold bonding. I can bond
the two and then use them but then I come back a day later and it
simply won't work and I then go through the procedure to 'rebond' the
phone and pocketpc. I have tried simply turning the phone and pocketpc
off to reset but that never fixes it. The PocketPC even has the phone
still listed as a device the PocketPC is bonded with but for some
reason I have to rebond this and this is almost a daily occurence and
I've been doing this for weeks now. Any idea what's causing this? I
do think it's connected to the phone because as well I have another
PocketPC I bond this phone with and I'm having the same problem with
that.