Garage Door in question:
Chamberlain 41A5021-1E ½ HP Security +

Problem:
With the open/closing button mounted on the wall, it has started not
closing unless you keep the button pushed down until it is closed
completely. At any time during the closing, you release the button,
it will reverse and open right back up. BTW, it opens with no
problems.

With the remote (with fresh batteries), it will not close or even
start to close at all but will open fine. When telling it to close,
all it does is flash the light 10 times without even trying to close,
even holding the button down like with the wall mounted button
mentioned above.

Both of the above mentioned started messing up at the same time so the
problem is most likely not the remote or wall mounted button.

Is this a known thingy or anyone have a suggestion for things to check
that a humble idiot can handle?

Regards,
Ed