Car overheating, engine coolant mixed with oil (bad head gasket?)?

the garage cant held responsible for u because they only doing major service for u...if they had change ur head gasket and then the coolant and oil mixed again....then u can charge them...but u had only done major service with them,....so u cant depend on them for wat had happened for your car....actually you should always check your engine oil level and coolant level and make a record so u can know if something happen..now the oil and coolant had mixed and it look like a peanut butter...u have to overhaul it...the best advice i can give u...make a full overhaul,dont just change head gasket because when u change head gasket...they just will take off ur head cylinder and just change the gasket...wat bout the oil+coolant in piston and crankshaft...so make a full overhaul for ur safety and make sure u done with a good and trustworthy workshop or service centre...hope this help u my fren