I am running below menioned SOQL query in my code- 

'select Id, Name,BILLINGSTREET, BILLINGCITY,'+ BILLINGSTATE,BILLINGPOSTALCODE,BILLINGCOUNTRY,CORPORATE_MEMBERSHIP_FORCED_LAPSE_DATE__C,'+
 'SHIPPINGSTREET,SHIPPINGCITY, SHIPPINGSTATE, SHIPPINGPOSTALCODE, SHIPPINGCOUNTRY, PHONE,FAX,'+ 'ACCOUNTSOURCE, Billing_Country_Code__c,Shipping_Country_Code__c,'+
        '(Select Id, MD_Head_of_Household__c, Salutation, firstName, LastName, MailingStreet,MailingCity, MailingState, MailingCountry,'  +
            'MailingPostalCode,Birthdate,Email,HomePhone,MobilePhone from Contacts) ' +
       'from Account where Sync__c = false AND Sync_Timestamp__c >=: startDateTime AND IsDeleted = FALSE order by Sync_Timestamp__c,Id ASC limit '+qLimit+' Offset '+qOffset';

This is query is working fine is TST sandbox but it is giving SOQL query timeout exception in UAT sandbox.
Both sandboxes are Full copy sandboxes and having same data.

Any hep/suggestion would be greatly appreciated.

I am running below menioned SOQL query in my code- 

'select Id, Name,BILLINGSTREET, BILLINGCITY,'+ BILLINGSTATE,BILLINGPOSTALCODE,BILLINGCOUNTRY,CORPORATE_MEMBERSHIP_FORCED_LAPSE_DATE__C,'+
 'SHIPPINGSTREET,SHIPPINGCITY, SHIPPINGSTATE, SHIPPINGPOSTALCODE, SHIPPINGCOUNTRY, PHONE,FAX,'+ 'ACCOUNTSOURCE, Billing_Country_Code__c,Shipping_Country_Code__c,'+
        '(Select Id, MD_Head_of_Household__c, Salutation, firstName, LastName, MailingStreet,MailingCity, MailingState, MailingCountry,'  +
            'MailingPostalCode,Birthdate,Email,HomePhone,MobilePhone from Contacts) ' +
       'from Account where Sync__c = false AND Sync_Timestamp__c >=: startDateTime AND IsDeleted = FALSE order by Sync_Timestamp__c,Id ASC limit '+qLimit+' Offset '+qOffset';

This is query is working fine is TST sandbox but it is giving SOQL query timeout exception in UAT sandbox.
Both sandboxes are Full copy sandboxes and having same data.

Any hep/suggestion would be greatly appreciated.