I need help

The Manager has no right to say such thing. As a consumer you have every right to buy any goods of your choice and if the product suffers from any defect after purchase, the service centre is bound to repair or give service to you within the warranty period.

you can write to the Co about the issue.

Such like attitude amounts to unfair trade practice and challnageable under CP Act.

KINDLY NOTE THAT.

1.YOU MAY PURCHASE ANY PRODUCT WITH PURCHASE INVOICE , THEY WILL MENTION GUARANTEE IF ANY.

2. YOU MAY INFORM THE MANUGACTURER REGARDING THE SAID PURCHASE AND MENTION ABOUT PREVIOUS BEHAVIOUR OF SAID EMPLOYEE OF SERVICE  CENTRE.

3. KEEP COPY OF SAID LETTER SO THAT IN CASE OF ANY NEED IN FUTURE FOR SERVICING  AND ANY PROBLEM FROM SAID PERSON. YOU MAY FILE A COMPLAINT BEFORE CONSUMER COURT MENTIONING ALL FACTS AND DEFICIENCY IN SERVICE. YOU WILL SUCCEED. GOOD LUCK.