sql select with a simple join does not works ...

[steph march]

greetings
My name is Stephane and
I'm pleased to meet you all.

As said in the topic, really, I have a problem.
I'm building a sms notification with:
C (libmysql api), Mysql and a simple php webpage.

here's the tables definitions :
2 tables
receive_audit
subscribers

Receive_audit fields definitions:

uid (timestamp, YYYY-MM-DD HH:MM:00, pk, not null, )
provider (varchar 30, not null)

susbscribers fields definitions:

idx (int 11, pk, not null, auto incr.)
send_to (varchar 12, not null, the cellphone to send sms to)
provider (varchar 30, not null)
commentsms (varchar 60, not null, owner name of cellphone)

in short, the receive_audit table contain arrival of providers
at the dock of my grocery store.

the subscribers table contain peoples interested to get notified
of specifics arrivals (ex.: Pepsi, Miller, Coke, Budweiser)

I tried a simple inner join, 0 row's

SELECT
`receive_audit`.`uid`
, `receive_audit`.`provider`
, `subscribers`.`send_to`
, `subscribers`.`commentsms`
FROM
`receivmanifest`.`receive_audit`
INNER JOIN `receivmanifest`.`subscribers`
ON (`receive_audit`.`provider` = `subscribers`.`provider`)
GROUP BY `receive_audit`.`provider`
ORDER BY `receive_audit`.`uid` ASC;

Can you suggest any modification let me know.
I tried trim function.

I already analyzed the result set which should be 3 rows.

help the newbie thanks !
Stephane