Sounds like you have a couple of things to work on here and I know
it's frustrating.
First, is she the only dog and if not, what is her 'pecking' order in
your pack?
Has she been checked by the vet to make sure there are no medical
issues?
Has she always done this behavior or did it start recently or after
you brought another dog or baby in your home?
Has she ever been scolded for peeing on the floor?
If she is the only dog and no humans have moved in after her arrival,
she isn't 'marking' her territory. If she isn't the only dog but was
there first and another dog was added or baby or roommate moved in, she
is 'marking' her territory.
If she is perfectly healthy AND was previously housebroken until
recently AND she is the only dog AND she was never scolded for 'going' in
the house, you must go right back to 'kindergarten' and re-teach her to
go outside.
If you or anyone else has ever scolded her for 'going' in the house
(even ONCE. dogs don't forget this), she will exhibit this behavior.
If you haven't used a product on your floors that eliminate the urine
or feces odor, she will continue to do her 'business' inside. Dogs
usually sniff out the same places they have gone and do their 'business'
there.
If your dog isn't on a regular feeding and water schedule and you
forget to take her out when it's time, she will 'go' where and when she
needs to.
Remember this, a dog can hold it's bladder one hour plus one for
every month they are old. Your dog is four months old. Your dog should be
able to 'hold' it for five hours providing she was housebroken properly
in the beginning. This means when you began the training, you had her
on a feeding and water schedule, you took her out constantly to the same
spot every time, you told her to "go potty" or "hurry up" then praised
her lavishly when she did her 'business' then took her right back
inside. No play time, no sniffing around. Right back in the house.
Having a feeding schedule is critical for housebreaking. Keeping a
watchful eye on your dog and taking her out BEFORE she has had an
accident is very important. Praising her for 'going' is also very important.
If you don't have a playpen (along with a crate) to put your dog in
so you can watch her, you will have to tether her to you. This is a pain
but you will always be able to watch her this way.
I know it sounds like a lot of work but you must get a handle on this
before you get to the point where you want to rehome your dog and that
would be a shame because this is something that is easily fixed.
Sit down with a cup of coffee, a soda or a stiff drink and think
about what went wrong with your dog. Go through the steps and ask yourself
if you did everything right to teach your dog to 'go' outside. Ask
yourself if there was anything you could have done better, is there
something you did that made the situation worse?
You can wipe the slate clean (as if your dog was eight weeks old) and
start over. Take her outside on a leash to a potty area, tell her to
"go potty". Give her some time (but not too long) to 'go'. You should be
able to read her body language by now and you know if she's going to
'go' or not.
If she doesn't do anything, don't say anything to her. Take her back
inside. If you see her sniffing around in the house, take her right
back outside and do the same thing all over again. If you catch her in the
middle of peeing in the house, yell "NO"!, scoop her up (don't be mad
at her), hold her in your arms and take her to her potty spot then let
her 'go'.
If she goes, praise, praise, praise. Take her back inside.
Success of this behavior depends on you. Be consistent, be patient,
be fair.
I hope this has helped you at least a little bit.