Subquery returning null - mysql

Question

Got this confusing issue where I need to get data from several tables and join them into one result.
This query was working fine:
select simcard.*,customer.name as cuname,mi,ma,co, tot from simcard, customer,
(SELECT s.sim_id AS ssim_id, min(datetime) AS mi, max(datetime) AS ma, FLOOR(sum(t.WEIGHT) / 1000) AS tot,
(SELECT count(datetime)
FROM transactions t
WHERE (t.SIM_ID = ssim_id) AND t.ROWTYPE LIKE '$D' GROUP BY t.sim_id) as co
FROM simcard s, transactions t
WHERE (s.sim_id = t.sim_id) AND t.ROWTYPE LIKE '$Z'
AND ( s.customer_id =1 ) GROUP BY s.sim_id) as T
WHERE (sim_id = ssim_id) AND (simcard.customer_id = customer.id) GROUP BY simcard.SIM_ID
But when I add a new customer and new simcard to that customer, it will return empty. I'm guessing this is because there is not transaction with that sim_id in the transaction able.
I've tried to left join but I'm just getting errors.
I've narrowed it down to the first subquery, removing the second one did not result in an non-empty result, but because both subqueries uses the transaction table I'm guessing that both will need some left join.
Structure:
DROP TABLE IF EXISTS `customer`;
CREATE TABLE IF NOT EXISTS `customer` (
`ID` int(10) NOT NULL AUTO_INCREMENT,
`NAME` varchar(40) DEFAULT NULL,
`API` int(11) NOT NULL DEFAULT 0,
PRIMARY KEY (`ID`),
KEY `CUSTOMER_ID` (`ID`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
-- --------------------------------------------------------
--
-- Tabellstruktur `simcard`
--
DROP TABLE IF EXISTS `simcard`;
CREATE TABLE IF NOT EXISTS `simcard` (
`ID` int(11) NOT NULL AUTO_INCREMENT,
`SIM_ID` char(20) DEFAULT NULL,
`CUSTOMER_ID` char(10) DEFAULT NULL,
`SCALES_ID` char(10) DEFAULT NULL,
`NAME` varchar(40) DEFAULT NULL,
`ACTIVE` char(1) DEFAULT 'N',
`EMAIL` varchar(255) DEFAULT NULL,
`TARGET_WEIGHT` varchar(255) DEFAULT NULL,
`LICENSE` tinyint(1) NOT NULL DEFAULT 0,
PRIMARY KEY (`ID`),
KEY `SIM_ID` (`SIM_ID`),
KEY `CUSTOMER_ID` (`CUSTOMER_ID`),
KEY `SCALES_ID` (`SCALES_ID`),
KEY `SIM_ID_2` (`SIM_ID`,`CUSTOMER_ID`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
-- --------------------------------------------------------
--
-- Tabellstruktur `transactions`
--
DROP TABLE IF EXISTS `transactions`;
CREATE TABLE IF NOT EXISTS `transactions` (
`ID` int(11) NOT NULL AUTO_INCREMENT,
`SCALES_ID` char(10) DEFAULT NULL,
`SIM_ID` char(20) DEFAULT NULL,
`ROWTYPE` char(2) DEFAULT NULL,
`DATETIME` datetime DEFAULT NULL,
`TRANSACTIONTIME` int(11) DEFAULT NULL,
`NAME` varchar(255) DEFAULT NULL,
`TRANSACTIONNUMBER` int(11) DEFAULT NULL,
`DATA0` varchar(255) DEFAULT NULL,
`DATA1` varchar(255) DEFAULT NULL,
`DATA2` varchar(255) DEFAULT NULL,
`DATA3` varchar(255) DEFAULT NULL,
`DATA4` varchar(255) DEFAULT NULL,
`DATA5` varchar(255) DEFAULT NULL,
`DATA6` varchar(255) DEFAULT NULL,
`DATA7` varchar(255) DEFAULT NULL,
`DATA8` varchar(255) DEFAULT NULL,
`MEMORY` varchar(255) DEFAULT NULL,
`MATERIAL` varchar(255) DEFAULT NULL,
`DENSITY` int(11) DEFAULT NULL,
`VEHICLETYPE` char(1) DEFAULT NULL,
`TOOLNAME` varchar(255) DEFAULT NULL,
`WEIGHT` int(11) DEFAULT NULL,
`TRANSACTIONID` int(11) DEFAULT NULL,
`group_id` int(11) NOT NULL DEFAULT 0,
PRIMARY KEY (`ID`),
KEY `SIM_ID` (`SIM_ID`),
KEY `TRANSACTIONID` (`TRANSACTIONID`),
KEY `SCALES_ID` (`SCALES_ID`),
KEY `SIM_ID_2` (`SIM_ID`,`TRANSACTIONID`),
KEY `idx_transactions_ROWTYPE` (`ROWTYPE`),
KEY `idx_transactions_DATETIME` (`DATETIME`),
KEY `idx_transactions_DATA0` (`DATA0`),
KEY `idx_transactions_DATA1` (`DATA1`),
KEY `idx_transactions_DATA2` (`DATA2`),
KEY `idx_transactions_DATA3` (`DATA3`),
KEY `idx_transactions_DATA4` (`DATA4`),
KEY `idx_transactions_DATA5` (`DATA5`),
KEY `idx_transactions_DATA6` (`DATA6`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
COMMIT;
Expected result:
ID SIM_ID CUSTOMER_ID SCALES_ID NAME ACTIVE EMAIL TARGET_WEIGHT LICENSE cuname mi ma co tot
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
8 10100421287868 1 61 M-61M Y NULL NULL 0 testcustomer 2018-04-26 00:00:00 2018-08-08 00:00:00 14908 529446