Dear …
RE: Storage Space
We notice that you have __(started/been)__ using the __(type of storage space)__ to store your __(type of goods)__. At this time we must inform you that this __(area/space)__ has already been __(designated/assigned)__ __(for type of use/to Name of other tenant/etc.)__. Unfortunately, due to the limited space in this __(name of area)__, we have to ask you to discontinue storing your __(type of goods)__ there.
In our attempt to accommodate all our tenants’ storage needs, alternatively, we can offer you storage for your __(type of goods)__ in the __(name of area(s)__. There is ample space in __(this/these)__ area(s) and you are welcome to use __(it/them)__ anytime. We trust you will find this as satisfactory means for your storage requirements.
Thank you for your understanding and cooperation in this matter.
Yours very truly,