had the from lower arm replaced an when driving home the car is going straight but the steering wheel is slight to the right but going straight ahead? can anyone help thanks 

Tell garage which done wheel alignment your steering wheel not straight. I suppose wheel alignment has been done?

so would hope they have done it but can’t really tell, 

what els could be the problem if they have done it. thanks 

Sounds like an alignment problem.

Not all garages have the equipment to do realignment, it's expensive and takes up a lot of room (a whole "bay"). Those without the equipment will either take your vehicle to another business that does have the equipment to get it done, or will simply leave it up to you to take it somewhere yourself.

Does it happen to say anything about having paid for realignment in the invoice?

Go back to them ASAP, be polite, show them the problem, and find out what the situation is regarding realignment. Either they simply forgot to advise you to take it somewhere that does realignment yourself, or they, or the people they subcontracted it out to, failed to do an adequate job. In the latter case understand that there are several possible reasons why they failed, they may have gotten distracted for instance, it happens. Politely give them the opportunity to put it right. If what you previously paid them covered having the realignment done, you should expect them to redo it at their expense. If they're being difficult about it you could also be well within your rights to get a different company to do it and then recover the cost from the original company.

They'll probably tell you it doesn't need aligning because the track rod end wasn't replaced/adjusted.  That is true but some wishbones are built to tighter tolerances than others.  Generally they will need alignment done after fitting just one aftermarket arm, but a pair should even it out.

all sorted now thank you