On a sunny day (Mon, 19 Mar 2018 09:44:01 +0000) it happened druck
 wrote in :

>On 18/03/18 20:03, The Natural Philosopher wrote:
>> wifi is not peer to peer. Yu have effective masters and clients. If =
> you
>> dont have master software running on the pi nothing will 'connect to it=
>'
>
>WiFi supports both infrastructure and adhoc modes, so both client/access =
>
>point and peer to peer.
>
>---druck

It is always difficult to answer the OP question without more info,
much better he should read the linux [wireless] networking howto.
There are some simple commands you can enter in a terminal as root
to find out about your network status, like
 iwconfig
(and ifconfig of course), and
 iwlist scanning
to see what clients, if any, it sees.

May take some time, but guessing takes much longer...

Also if it suddenly stops working: anybody else close by on that channel?
Now I am guessing myself ;-(
Change channel?

I had an old pi with a wifi adaptor as access point.
After things got hacked everything is wired here.
Can always plug it back in if needed.
For music local short distance use bluetooth works fine.
Even then I use an ebay bluetooth transmitter that takes audio in...
No setup and can be used on any audio output.
Anyways all the high power WiFi is not good for you,
do not want it next to my head.
I know it is big business, but so are opiods and other drugs.

--- SoupGate-Win32 v1.05